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Engine Controls - Self-Diagnostics Suzuki Grand Vitara I

Testing & Diagnostics 6 illustrations ~20955 words

DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION

DTCSystem AffectedCondition
P0101MAF Sensor CircuitPoor MAF Sensor Performance
P0102MAF Sensor CircuitMAF Sensor Low Input
P0103MAF Sensor CircuitMAF Sensor High Input
P0111IAT Sensor CircuitCircuit Range/Performance Problem
P0112IAT Sensor CircuitLow IAT Sensor Circuit Input
P0113IAT Sensor CircuitHigh IAT Sensor Circuit Input
P0116ECT Sensor CircuitECT Sensor Circuit Range/Performance Problem
P0117ECT Sensor CircuitLow ECT Sensor Circuit Input
P0118ECT Sensor CircuitHigh ECT Sensor Circuit Input
P0121TP Sensor CircuitPoor TP Sensor Performance
P0122TP Sensor CircuitLow TP Sensor Circuit Input
P0123TP Sensor CircuitHigh TP Sensor Circuit Input
P0125ECT Sensor CircuitInsufficient Coolant Temperature For Closed Loop Operation
P0131 (1)HO2S No. 1 CircuitLow HO2S No. 1 Circuit Input
P0132 (1)HO2S No. 1 CircuitHigh HO2S No. 1 Circuit Input
P0133 (1)HO2S No. 1 CircuitSlow Response Of HO2S No. 1 Circuit
P0134 (1)HO2S No. 1 CircuitNo HO2S No. 1 Circuit Activity Detected
P0135 (1)HO2S No. 1 Heater CircuitHO2S No. 1 Heater Circuit Malfunction
P0136 (1)HO2S No. 2 CircuitHO2S No. 2 Circuit Malfunction
P0141 (1)HO2S No. 2 Heater CircuitHO2S No. 2 Heater Circuit Malfunction
P0151 (2)HO2S No. 1 CircuitLow HO2S No. 1 Circuit Input
P0152 (2)HO2S No. 1 CircuitHigh HO2S No. 1 Circuit Input
P0153 (2)HO2S No. 1 CircuitSlow Response Of HO2S No. 1 Circuit
P0154 (2)HO2S No. 1 CircuitNo HO2S No. 1 Circuit Activity Detected
P0155 (2)HO2S No. 1 Heater CircuitHO2S No. 1 Heater Circuit Malfunction
P0156 (2)HO2S No. 2 CircuitHO2S No. 2 Circuit Malfunction
P0161 (2)HO2S No. 2 Heater CircuitHO2S No. 2 Heater Circuit Malfunction
P0171 (1)Fuel System LeanTotal Fuel Trim Is Greater Than Allowed Specification
P0172 (1)Fuel System RichTotal Fuel Trim Is Less Than Allowed Specification
P0174 (2)Fuel System LeanTotal Fuel Trim Is Greater Than Allowed Specification
P0175 (2)Fuel System RichTotal Fuel Trim Is Less Than Allowed Specification
P0300Random Misfire DetectedElectrical Or Mechanical Misfire (Catalyst Damaging)
P0301Cylinder No. 1 MisfireElectrical Or Mechanical Misfire Common To One Cylinder
P0302Cylinder No. 2 MisfireElectrical Or Mechanical Misfire Common To One Cylinder
P0303Cylinder No. 3 MisfireElectrical Or Mechanical Misfire Common To One Cylinder
P0304Cylinder No. 4 MisfireElectrical Or Mechanical Misfire Common To One Cylinder
P0305Cylinder No. 5 MisfireElectrical Or Mechanical Misfire Common To One Cylinder
P0306Cylinder No. 6 MisfireElectrical Or Mechanical Misfire Common To One Cylinder
P0335CKP Sensor CircuitNo CKP Sensor Signal (Engine Running)
P0340CMP Sensor CircuitNo CMP Sensor Signal For 2 Seconds During Engine Cranking
P0400EGR Flow MalfunctionExcessive Or Insufficient EGR Flow
P0420 (1)Catalyst Efficiency LowHO2S No. 1 & 2 Output Is Similar
P0430 (2)Catalyst Efficiency LowHO2S No. 1 & 2 Output Is Similar
P0440EVAP Emission Control SystemEVAP System Leak Detected
P0450EVAP System Pressure SensorPressure Sensor Circuit Open Or Shorted To Ground
P0451EVAP System Pressure SensorPressure Sensor Range/Performance Problem
P0455EVAP SystemExcessive Leakage From EVAP System Detected
P0461Fuel Level Sensor CircuitPoor Fuel Level Sensor Circuit Performance
P0463Fuel Level Sensor CircuitHigh Voltage Input
P0500Vehicle Speed Sensor MalfunctionNo Signal During Fuel-Cut
P0505Idle Control System MalfunctionTarget Idle Speed Not Obtained
P0601PCM Memory Check Sum ErrorData Write Error
P1408MDP Sensor CircuitMDP Sensor Circuit Open or Shorted To Ground
P1410Fuel Tank Pressure Control SystemLow Voltage Signal With High Fuel Level Reading
P1450Barometric Pressure SensorLow Or High Input
P1451Barometric Pressure SensorBarometric Pressure Sensor Performance Problem During Cranking
P1500Engine Starter Signal CircuitNo Input Or Constant Input From Starter Signal Circuit
P1510PCM Back-Up Power Supply MalfunctionNo Back-Up Power Supply After Engine Start
(1) These codes apply to Bank No. 1. (2) These codes apply to Bank No. 2.
(1)These codes apply to Bank No. 1.
(2)These codes apply to Bank No. 2.

DTC IDENTIFICATION

CIRCUIT TESTS

Note. See PIN VOLTAGE/CIRCUIT RESISTANCE CHARTS article for PCM connector and wire terminal identification.

A-1: MALFUNCTION INDICATOR LIGHT (MIL) INOPERATIVE

When ignition is on, PCM energizes main relay. As PCM is supplied with ignition power, MIL turns on. After engine starts, MIL will turn off if no malfunction is detected. If a malfunction is detected, MIL will remain on until system is repaired.

  1. Remove PCM cover, located below right side of instrument panel. Turn ignition on. Using DVOM, measure voltage (backprobe) between ground and PCM 28-pin connector "D" terminal No. 3 (Black/White wire). If 10-14 volts exists, go to step 3 . If 10-14 volts does not exist, go to next step.
  2. Check for blown BATT fuse No. 1 (80-amp) or IG fuse No. 3 (60-amp) in underhood fuse/relay center, located on right fenderwell. If BATT and IG fuses are okay, check for blown IG METER fuse No. 21 (20-amp) in instrument panel fuse block. If fuses are okay, check for open or poor connection in Black/White wire between PCM and fuse block. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary.
  3. Using jumper wire, ground PCM 35-pin connector "A" terminal No. 34 (Violet/Yellow wire). Turn ignition on. If MIL comes on, go to «A-3: PCM POWER & GROUND CIRCUIT CHECK/ENGINE NO START»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics__a-3-pcm-power-ground-circuit) . If MIL does not come on, check for bad MIL bulb. If MIL bulb is okay, check for open in Black/White wire between fuse block and MIL or Violet/Yellow wire between PCM and MIL. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary.

A-2: MALFUNCTION INDICATOR LIGHT (MIL) REMAINS ON

When ignition is on, PCM energizes main relay. As PCM is supplied with ignition power, MIL turns on. After engine starts, MIL will turn off if no malfunction is detected. If a malfunction is detected, MIL will remain on until system is repaired.

  1. Connect scan tool to Data Link Connector (DLC). Attempt to retrieve DTCs with ignition on, engine off. If any DTCs are displayed, see «DIAGNOSTIC TESTS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics) . If no DTCs are displayed, go to next step.
  2. Turn ignition off. Remove PCM cover, located below right side of instrument panel. Disconnect PCM connectors. Turn ignition on. If MIL comes on, repair short to ground in Violet/Yellow wire between MIL bulb and PCM connector. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. If MIL does not come on, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

A-3: PCM POWER & GROUND CIRCUIT CHECK/ENGINE NO START

  1. Listen to main relay in instrument panel fuse block while ignition switch is cycled on, then off. (Scheme 14) If operating sound is heard at relay, go to step 5. If no sound is heard, check FI fuse No. 8 (15-amp) in underhood fuse/relay center, located on right fenderwell. If fuse is okay, go to next step. If fuse is blown, check affected circuits for a short. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary.
  2. Turn ignition off and remove main relay. Check for poor connection at main relay. Repair as necessary. If connection is okay, measure resistance of main relay between terminals "C" and "D". (Scheme 15) Resistance should be 70-110 ohms at approximately 68° F (20° C). Check continuity of main relay between terminals "A" and "B". Continuity should not exist. Apply battery voltage between terminals "C" and "D". Continuity should now exist between terminals "A" and "B". Replace relay if continuity or resistance is not as specified. If relay tests okay, go to next step.
  3. Turn ignition off. Install main relay. Remove PCM cover, located below right side of instrument panel. Check for poor connection at PCM 28-pin connector "D" terminals No. 3 (Black/White wire), No. 20 and No. 21 (Blue/Black wires). Check for poor connection at PCM 35-pin connector "A" terminal No. 8 (Blue wire). Repair as necessary. If PCM connections are okay, go to next step.
  4. Disconnect PCM connectors. Turn ignition on. Using DVOM, measure voltage between ground and PCM 28-pin connector "D" terminal No. 3 (Black/White wire). If 10-14 volts does not exist, repair open in Black/White wire between PCM and IG METER fuse No. 21 (20-amp). See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. If 10-14 volts exists, measure voltage between ground and PCM 35-pin connector "A" terminal No. 8 (Blue wire). If 10-14 volts exists, go to next step. If 10-14 volts does not exist, check for open in Blue wire between PCM and main relay or Black/Red wire between main relay and FI fuse No. 8 (15-amp). Repair as necessary.
  5. Using jumper wire, ground PCM 35-pin connector "A" terminal No. 8 (Blue wire). Turn ignition on. Using DVOM, measure voltage between PCM 28-pin connector "D" terminal No. 20 (Blue/Black wire). If 10-14 volts does not exist, go to next step. If 10-14 volts exists, check for poor PCM grounding. Check Black/Green wire, Black/Orange wire and Black/Blue wire for open. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. If PCM ground connections and wiring are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article.
  6. Listen to main relay in instrument panel fuse block. If operating sound is heard at main relay, recheck main relay following procedures in step 2. If no sound is heard from main relay, check for open in Blue wire between PCM and main relay or Black/Red wire between main relay and FI fuse No. 8 (15-amp). Repair as necessary.

Scheme 14

Scheme 14
Scheme 14

Scheme 15

Scheme 15
Scheme 15

Condition

DTC is set when intake air flow measured by MAF sensor does not agree with calculated intake air flow calculated by Powertrain Control Module (PCM) using manifold absolute pressure, barometric pressure and engine speed. MIL is illuminated when PCM detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. Plugged or leaking air intake system.
  2. MAF sensor or circuit malfunction.
  3. Manifold Absolute Pressure (MAP) sensor or circuit malfunction.
  4. PCM malfunction.

DTC Confirmation Test

  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Ensure DTCs P0102, P0103, P0335 P1408 and P1451 are not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle with engine speed at 3000-4500 RPM. Stop vehicle. Check for DTC P0101. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.

Diagnosis & Repair Procedure

  1. Visually inspect for any obstructions or leaks in MAF sensor ducting. Repair as necessary. If visual inspection does not reveal any problems, turn ignition off. Connect scan tool to Data Link Connector (DLC). Start engine and allow it to reach normal operating temperature. Select MAF value parameter on scan tool. Increase engine speed to 2500 RPM. Display on scan tool should read 8.2-15.0 g/sec. Return engine to idle. Display on scan tool should read 2.5-4.6 g/sec. If reading is not as specified, go to step 5 . If reading is as specified, go to next step.
  2. Turn ignition off. Disconnect MAF sensor harness connector. Turn ignition on. Using DVOM, measure voltage between ground and MAF sensor harness connector terminal No. 3 (Blue/Black wire). If 10-14 volts exists, go to next step. If 10-14 volts does not exist, repair open in Blue/Black wire. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Retest system.
  3. Reconnect MAF sensor harness connector. Remove PCM cover, located below right side of instrument panel. Connect DVOM (backprobe) between PCM 26-pin connector "B" terminals No. 20 (Gray/Yellow wire) and No. 23 (Violet/White wire). With ignition switch in RUN position, 0-.5 volt should exist. Start and idle engine. DVOM should display 1.0-1.5 volts. If readings are not as specified, go to next step. If readings are as specified, check for poor connection at PCM 26-pin connector "B" terminals No. 20 (Gray/Yellow wire) and No. 23 (Violet/White wire). Repair as necessary. If PCM connections are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  4. Check for open in Gray/Yellow wire or Violet/White wire between PCM and MAF sensor. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary. If wiring between PCM and MAF sensor is okay, replace MAF sensor. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  5. Connect DVOM (backprobe) between PCM 26-pin connector "B" terminals No. 13 (Red/White wire) and No. 20 (Gray/Yellow wire). With ignition switch in RUN position, 4.5-5.5 volts should exist. Start and idle engine. DVOM should display 1.5-2.5 volts. If readings are as specified, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If readings are not as specified, a Manifold Differential Pressure (MDP) sensor problem exists. See «DTC P1408: MANIFOLD DIFFERENTIAL PRESSURE (MDP) SENSOR CIRCUIT MALFUNCTION»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics) .

DTC is set when MAF sensor output voltage is less than 0.3 volts for 1 second with engine running. Possible causes are

  1. MAF sensor or circuit malfunction.
  2. PCM malfunction.

Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article. Start engine and allow it to idle for 10 seconds. Check for DTC P0102. See RETRIEVING DTCS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.

  1. Turn ignition off. Disconnect MAF sensor harness connector. Turn ignition on. Using DVOM, measure voltage between ground and MAF sensor harness connector terminal No. 3 (Blue/Black wire). Reading should be 10-14 volts. If voltage is as specified, go to next step. If voltage is not as specified, repair open in Blue/Black wire between MAF sensor and main relay. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Retest system.
  2. Turn ignition off. Reconnect MAF sensor harness connector. Remove PCM cover, located below right side of instrument panel. Connect DVOM (backprobe) between PCM 26-pin connector "B" terminals No. 20 (Gray/Yellow wire) and No. 23 (Violet/White wire). If reading is not .5-1.0 volt, go to next step. If reading is .5-1.0 volt, check for poor PCM connection. Repair as necessary. If connections are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  3. Check for open in Gray/Yellow wire or Violet/White wire between PCM and MAF sensor. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Check for poor connection at MAF sensor. Repair as necessary. If wiring and connections are okay, replace MAF sensor. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC is set when MAF sensor output voltage is more than 5 volts for 1 seconds with engine running. Possible causes are

  1. MAF sensor or circuit malfunction.
  2. PCM malfunction.

Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article. Start engine and allow it to idle for 10 seconds. Check for DTC P0103. See RETRIEVING DTCS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.

  1. Remove PCM cover, located below right side of instrument panel. Turn ignition on. Connect DVOM (backprobe) between PCM 26-pin connector "B" terminals No. 20 (Gray/Yellow wire) and No. 23 (Violet/White wire). If reading is .5-1.0 volt, leave DVOM connected and go to next step. If reading is less than .5 volt, check for an open in Violet/White wire between MAF sensor and PCM. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. If reading is more than one volt, check for short to power in Violet/White wire. Repair as necessary. If wiring is okay, replace MAF sensor. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  2. Start engine. With DVOM still connected between PCM 26-pin connector "B" terminals No. 20 (Gray/Yellow wire) and No. 23 (Violet/White wire), note voltage reading. If reading does not rise within 5-volt range while engine speed is increased, replace MAF sensor. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system. If reading rises within 5-volt range while engine speed is increased, check for an intermittent problem. See «TROUBLE SHOOTING - NO CODES»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes) article. If all checks are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article.

DTC is set when variation in intake air temperature is less than predetermined. MIL is illuminated when Powertrain Control Module (PCM) detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. IAT sensor or circuit malfunction.
  2. PCM malfunction.
  1. Ensure engine coolant temperature is 14-86°F (-10-30°C) when vehicle is first started, vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Ensure DTCs P0101, P0102, P0103, P0112, P0113, P0116, P0117, P0118, and P0125 are not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle at speeds of 35 MPH or more for 10 minutes. Stop vehicle and allow it to idle for one minute. Check for DTC P0111. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.

Scheme 16

Scheme 16: Diagnosis & Repair Procedure
Scheme 16: Diagnosis & Repair Procedure
  1. Ensure ignition is off. Disconnect IAT sensor harness connector. Check terminals of IAT sensor harness connector for poor contact. If poor terminal contact is found, repair as necessary and retest system. If connection is okay, remove IAT sensor from air cleaner and go to next step.
  2. Using an ohmmeter, measure resistance between IAT sensor terminals while immersed in a container of water. Heat water slowly and ensure resistance changes as specified. (Scheme 16) If resistance is as specified, go to next step. If resistance is not as specified, replace IAT sensor. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  3. Ensure IAT sensor is disconnected. Turn ignition on. Using DVOM, measure voltage at IAT sensor harness connector terminal No. 2 (Light Blue wire). If 4.5-5.5 volts exists, go to next step. If 4.5-5.5 volts does not exist, check for open in Light Blue wire between IAT sensor and PCM. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary. If Light Blue wire is okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  4. Check for open in Gray/Yellow wire between IAT sensor and PCM. Repair as necessary. If Gray/Yellow wire is okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC is set when IAT sensor output voltage is less than 0.16 volts for 5 seconds. MIL is illuminated when Powertrain Control Module (PCM) detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. IAT sensor or circuit malfunction.
  2. PCM malfunction.

Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article. Start engine and allow it to idle for 10 seconds. Check for DTC P0112. See RETRIEVING DTCS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.

  1. Turn ignition off. Disconnect IAT sensor harness connector. Turn ignition on. Using DVOM, measure voltage between ground and IAT sensor harness connector terminal No. 2 (Light Blue wire). If 4.5-5.5 volts exists, go to next step. If 4.5-5.5 volts does not exist, check Light Blue wire for short to ground between IAT sensor and PCM. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary. If Light Blue wire is okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  2. Remove IAT sensor from air cleaner. Using an ohmmeter, measure resistance between IAT sensor terminals while immersed in a container of water. Heat water slowly and ensure resistance changes as specified. (Scheme 16) If resistance is not as specified, replace IAT sensor. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system. If resistance is as specified, check for an intermittent problem. See «TROUBLE SHOOTING - NO CODES»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes) article. If all checks are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC is set when IAT sensor output voltage is more than 5 volts for 5 seconds. MIL is illuminated when Powertrain Control Module (PCM) detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. IAT sensor or circuit malfunction.
  2. PCM malfunction.

Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article. Start engine and allow it to idle for 10 seconds. Check for DTC P0113. See RETRIEVING DTCS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.

  1. Turn ignition off. Disconnect IAT sensor harness connector. Turn ignition on. Using DVOM, measure voltage between ground and IAT sensor harness connector terminal No. 2 (Light Blue wire). If 4.5-5.5 volts exists, go to next step. If 4.5-5.5 volts does not exist, check Light Blue wire for open or short to power between IAT sensor and PCM. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary. If Light Blue wire is okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  2. Turn ignition off. Using a fused jumper wire, connect IAT sensor harness connector terminals together. Turn ignition on. Measure voltage between ground and IAT sensor harness connector terminal No. 2 (Light Blue wire). If .15 volt or more exists, go to next step. If less than .15 volt exists, check IAT sensor operation following procedure in «DTC P0112: INTAKE AIR TEMPERATURE (IAT) SENSOR CIRCUIT LOW INPUT»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics) , step 2) . Repair as necessary.
  3. Check for an open or short in Gray/Yellow wire between IAT sensor and PCM. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary. If Gray/Yellow wire is okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC is set when engine coolant temperature fails to reach predetermined level after vehicle has been running for a predetermined time. Engine coolant temperature variation is less than predetermined. MIL is illuminated when Powertrain Control Module (PCM) detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. ECT sensor or circuit malfunction.
  2. Thermostat malfunction.
  3. PCM malfunction.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, engine coolant temperature is 86-140°F (30-60°C) when engine is first started, and barometric pressure is 74 kPa or more. Ensure DTCs P0117, P0118 and P0335 are not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to idle for more than 20 minutes. Turn ignition off. Start engine when engine coolant temperature is more than 158°F (70°C). Allow engine to idle for more than 15 minutes. Check for DTC P0116. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Select ECT-1 sensor parameter on scan tool. Warm engine to operating temperature. Select ECT-2 sensor parameter on scan tool. If difference between ECT-1 and ECT-2 is less than 1°F (1°C), go to step 3 . If difference between ECT-1 and ECT-2 is more than 1°F (1°C), go to next step.
  2. Check thermostat operation. If heater takes a long time to become effective, or coolant flows into radiator on cold start, remove thermostat for inspection. Replace as necessary and retest system. If thermostat operates properly, go to next step.
  3. Turn ignition off. Disconnect ECT sensor harness connector. Turn ignition on. Scan tool should display -40°F (-40°C). Jumper ECT sensor harness connector terminals together. Scan tool should display 401°F (205°C). If scan tool display is as specified, go to next step. If scan tool display is not as specified, check for open or short in Orange/Black wire or Gray/Yellow wire between ECT sensor and PCM. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. If wiring is okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  4. Test ECT sensor. See SYSTEM & COMPONENT TESTING article. Replace ECT sensor if resistance is not as specified. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If ECT sensor tests okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC is set when Power Control Module (PCM) detects ECT sensor input voltage is less than 0.16 volts for 5 seconds. Possible causes are

  1. ECT sensor or circuit malfunction.
  2. PCM malfunction.

Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article. Start engine and allow it to idle for 10 seconds. Check for DTC P0117. See RETRIEVING DTCS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.

  1. Turn ignition off. Disconnect ECT sensor harness connector. Turn ignition on. Using DVOM, measure voltage at ECT sensor harness connector terminal No. 1 (Orange/Black wire). If 4.5-5.5 volts exists, go to next step. If 4.5-5.5 volts does not exist, check Orange/Black wire for short to ground. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. If wire is okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  2. Test ECT sensor. See SYSTEM & COMPONENT TESTING article. Replace ECT sensor if resistance is not as specified. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If ECT sensor tests okay, check for poor connection to ECT sensor. If connection is okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC is set when Power Control Module (PCM) detects ECT sensor input voltage is more than 5 volts for 5 seconds. Possible causes are

  1. ECT sensor or circuit malfunction.
  2. PCM malfunction.

Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article. Start engine and allow it to idle for 10 seconds. Check for DTC P0118. See RETRIEVING DTCS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.

  1. Turn ignition off. Disconnect ECT sensor harness connector. Turn ignition on. Using DVOM, measure voltage at ECT sensor harness connector terminal No. 1 (Orange/Black wire). If 4.5-5.5 volts exists, go to next step. If 4.5-5.5 volts does not exist, check Orange/Black wire for open or short to power. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. If wire is okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  2. Turn ignition off. Connect a fused jumper wire between ECT sensor harness connector terminals No. 1 (Orange/Black wire) and No. 3 (Gray/Yellow wire). Turn ignition on. Using DVOM, measure voltage between ground and ECT sensor harness connector terminal No. 1 (Orange/Black wire). If less than .15 volt exists, go to next step. If .15 volt or more exists, check Gray/Yellow wires for open or poor connection between ECT sensor harness connector terminal No. 3 and PCM 26-pin connector "B" terminals No. 20 and 21. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary. If wiring and connections are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  3. Test ECT sensor. See SYSTEM & COMPONENT TESTING article. Replace ECT sensor if resistance is not as specified. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If ECT sensor tests okay, check for poor connection to ECT sensor. If connection is okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC is set when Powertrain Control Module (PCM) detects throttle opening is to small with vehicle operating under high load and high engine speed. DTC is also set when ECM detects throttle opening is to large with vehicle operating under low load and low engine speed. MIL is illuminated when ECM detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. Intake air system malfunction.
  2. TP sensor or circuit malfunction.
  3. ECM malfunction.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Ensure DTCs P0101, P0102, P0103, P0116, P0117 , P0118, P0122, P0123, P0335 and P1451 are not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle with engine speed at 3300-3700 RPM for 10 seconds. Stop vehicle and allow engine to idle for 10 seconds. Check for DTC P0121. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. Remove PCM cover, located below right side of instrument panel. Start engine and allow to reach normal operating temperature. Turn engine off. Connect DVOM (backprobe) between PCM 26-pin connector "B" terminals No. 12 (Red/Green wire) and No. 20 (Gray/Yellow wire). Turn ignition on. Measure voltage with throttle in closed and fully open positions. DVOM should display.35-.65 volts with throttle in closed position and 3.5-4.5 volts with throttle in fully open position. If voltage is as specified, go to next step. If voltage is not as specified, go to step 3.
  2. Visually inspect for any obstructions or leaks in MAF sensor ducting. Repair as necessary. If air intake system checks okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  3. Turn ignition off. Ensure there is clearance between fast idle cam and follow lever. Disconnect TP sensor harness connector. Using ohmmeter, measure resistance between TP sensor terminals No. 1 and 3. (Scheme 17) Resistance should be 4-6 k/ohms. Connect ohmmeter between TP sensor terminals No. 2 and 3. Resistance should vary 0-4.6 k/ohms according to throttle opening. If resistance is as specified, go to next step. If resistance is not as specified, replace TP sensor. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  4. Using DVOM, measure voltage between ground and TP sensor harness connector terminal No. 3 Gray/Red wire). If 4.5-5.5 volts exists, go to next step. If 4.5-5.5 volts does not exist, check for open in Gray/Red wire. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary. If Gray/Red wire is okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  5. Using ohmmeter, check continuity between ground and TP sensor harness connector terminal No. 1 (Gray/Yellow wire). If continuity exists, go to next step. If continuity does not exist, check for open in Gray/Yellow wire. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary. If Gray/Yellow wire is okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  6. Connect DVOM (backprobe) between ground and PCM 26-pin connector "B" terminals No. 12 (Red/Green wire). Turn ignition on. Loosen TP sensor retaining screws. Rotate TP sensor to achieve.35-.65 volt with throttle closed. Tighten TP sensor retaining screws. Fully open throttle. TP sensor reading should be 3.5-4.5 volts. If TP sensor voltage is within specification after adjustment, retest system. If correct TP sensor voltage cannot be obtained during adjustment, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

Scheme 17

Scheme 17
Scheme 17

DTC is set when Power Control Module (PCM) detects TP sensor voltage is less than 0.1 volt for 1 second. Possible causes are

  1. TP sensor or circuit malfunction.
  2. PCM malfunction.

Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article. Start engine and allow it to idle for 10 seconds. Check for DTC P0122. See RETRIEVING DTCS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.

  1. Turn ignition off. Disconnect TP sensor harness connector. Turn ignition on. Using DVOM, measure voltage between ground and TP sensor harness connector terminal No. 3 (Gray/Red wire). If 4.5-5.5 volts exists, go to next step. If 4.5-5.5 volts does not exist, check for open, short to ground or poor connection in Gray/Red wire. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary. If wiring and connections are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  2. Turn ignition off. Ensure there is clearance between fast idle cam and follow lever. Disconnect TP sensor harness connector. Using ohmmeter, measure resistance between TP sensor terminals No. 1 and 3. (Scheme 17) Resistance should be 4-6 k/ohms. Connect ohmmeter between TP sensor terminals No. 2 and 3. Resistance should vary 0-4.6 k/ohms according to throttle opening. If resistance is not as specified, replace TP sensor. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If resistance is as specified, go to next step.
  3. Check for open, short to ground or poor connection in Red/Green wire between PCM and TP sensor harness connector terminal No. 2. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary. If Red/Green wire is okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC is set when Power Control Module (PCM) detects TP sensor voltage is more than 4.8 volts for 1 second. Possible causes are

  1. TP sensor or circuit malfunction.
  2. PCM malfunction.

Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article. Start engine and allow it to idle for 10 seconds. Check for DTC P0123. See RETRIEVING DTCS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.

  1. Turn ignition off. Disconnect TP sensor harness connector. Turn ignition on. Using DVOM, measure voltage between ground and TP sensor harness connector terminal No. 3 (Gray/Red wire). If 4.5-5.5 volts exists, go to next step. If 4.5-5.5 volts does not exist, check for open or poor connection in Gray/Yellow wire. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Check for short to power in Gray/Red wire. Repair as necessary. If wiring and connections are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  2. Turn ignition off. Ensure there is clearance between fast idle cam and follow lever. Disconnect TP sensor harness connector. Using ohmmeter, measure resistance between TP sensor terminals No. 1 and 3. (Scheme 17) Resistance should be 4-6 k/ohms. Connect ohmmeter between TP sensor terminals No. 2 and 3. Resistance should vary 0-4.6 k/ohms according to throttle opening. If resistance is not as specified, replace TP sensor. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If resistance is as specified, go to next step.
  3. Check for short to power in Red/Green wire between PCM and TP sensor harness connector terminal No. 2. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary. If Red/Green wire is okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC is set when engine coolant temperature fails to reach predetermined level after vehicle has been driven. MIL is illuminated when Power Control Module (PCM) detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. ECT sensor or circuit malfunction.
  2. Engine cooling system malfunction.
  3. PCM malfunction.

Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, engine coolant temperature less than 86°F (30°C) when engine is first started, and barometric pressure is 74 kPa or more. Ensure DTCs P0117, P0118 and P0335 are not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article. Start engine and allow it to idle for 10 seconds. Check for DTC P0125. See RETRIEVING DTCS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.

  1. Turn ignition off. Connect scan tool to Data Link Connector (DLC). Start engine and warm to operating temperature. Idle engine. If ECT reading is less than 88°F (31°C), go to next step. If ECT reading is more than 88°F (31°C), go to step 4 .
  2. Turn ignition off. Connect a jumper wire between ECT sensor harness connector terminals No. 1 (Orange/Black wire) and No. 3 (Gray/Yellow wire). Turn ignition on. If ECT reading is 401°F (205°C), go to next step. If ECT reading is not 401°F (205°C), check for open in Orange/Black wire or Gray/Yellow wire between ECT sensor harness connector and PCM. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary. If Orange/Black wire and Gray/Yellow wire are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  3. Test ECT sensor. See SYSTEM & COMPONENT TESTING article. Replace ECT sensor if resistance is not as specified. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If ECT sensor tests okay, go to next step.
  4. Check thermostat operation. If heater takes a long time to become effective, or coolant flows into radiator on cold start, remove thermostat for inspection. Replace as necessary and retest system. If thermostat operates properly, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC P0131: HEATED OXYGEN SENSOR (HO2S) CIRCUIT VOLTAGE LOW BANK NO. 1 SENSOR NO. 1 (B1 S1)

Note. Before replacing HO2S B1 S1, inspect sensor for contamination. If contamination is present, determine cause and repair before installing a new HO2S B1 S1.

DTC is set when Heated Oxygen Sensor (HO2S) B1 S1 maximum output voltage is 0.4 volts or less. MIL is illuminated when Power Control Module (PCM) detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. HO2S B1 S1 or circuit malfunction.
  2. Fuel injector malfunction.
  3. Fuel pressure control system malfunction.
  4. PCM malfunction.
  5. Low fuel level.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Ensure DTC P0135 is not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle with engine speed at 2000-3000 RPM with throttle steady for one minute. Stop vehicle. Check for DTC P0131. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. Connect scan tool to Data Link Connector (DLC). Drive vehicle for at least 2 minutes at 2000 RPM or greater with engine coolant at 158°F (70°C) or greater. Observe OXYGEN SENSOR B1 S1 parameter on scan tool. If .4 volt or more is displayed, go to next step. If less than .4 volt is displayed, check for an intermittent problem. See «TROUBLE SHOOTING - NO CODES»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes) article. If all checks are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  2. Remove PCM cover, located below right side of instrument panel. Connect DVOM (backprobe) between PCM 26-pin connector "B" terminals No. 4 (Red wire) and No. 20 (Gray/Yellow wire). Start engine. Observe voltage while sharply increasing engine RPM and returning to idle. If reading is more than .1 volt when fuel is cut, go to next step. If reading is less than .1 volt when fuel is cut, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  3. Check HO2S B1 S1 Red wire and Gray/Yellow wire for opens or shorts. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair wiring or replace HO2S B1 S1 as necessary. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If HO2S B1 S1 Red wire and Gray/Yellow wire check okay, go to next step.
  4. Check fuel injector circuit. See «CIRCUIT TEST B-1: FUEL INJECTOR CIRCUIT INSPECTION»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-basic-diagnostic-procedures) in BASIC DIAGNOSTIC PROCEDURES article. Repair as necessary. If fuel injector circuit checks okay, go to next step.
  5. Measure resistance of fuel injectors on cylinders No. 1, 3 and 5. See INJECTOR RESISTANCE in SERVICE & ADJUSTMENTS article. Replace injector(s) as necessary. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If injector resistance is within specification, go to next step.
  6. Perform fuel pressure test. See «FUEL SYSTEM»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-basic-diagnostic-procedures__fuel-system) in BASIC DIAGNOSTIC PROCEDURES article. Repair as necessary. If fuel pressure is within specification, go to next step.
  7. Replace HO2S B1 S1. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system. If DTC P0131 resets, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC P0132: HEATED OXYGEN SENSOR (HO2S) NO. 1 CIRCUIT VOLTAGE HIGH BANK NO. 1 SENSOR NO. 1 (B1 S1)

Note. Before replacing HO2S B1 S1, inspect sensor for contamination. If contamination is present, determine cause and repair before installing a new HO2S B1 S1.

DTC is set when HO2S B1 S1 output voltage is 0.6-1.2 volts. MIL is illuminated when Power Control Module (PCM) detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. HO2S B1 S1 or circuit malfunction.
  2. PCM malfunction.
  3. Low fuel level.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Ensure DTC P0135 is not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle with engine speed at 2000-3000 RPM with throttle steady for one minute. Stop vehicle. Check for DTC P0132. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Observe OXYGEN SENSOR B1 S1 parameter on scan tool. If reading is more than one volt, go to next step. If reading is less than one volt, go to step 3 .
  2. Check Red wire between PCM and HO2S B1 S1 for short to power. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary. If Red wire is okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  3. Remove PCM cover, located below right side of instrument panel. Connect DVOM (backprobe) between PCM 26-pin connector terminals No. 4 (Red wire) and No. 20 (Gray/Yellow wire). Start engine. Observe voltage while sharply increasing engine RPM and returning to idle several times. If reading varies 0-1 volt, go to next step. If reading does not vary 0-1 volt, go to step 5 .
  4. Check for poor connection at PCM 26-pin connector "B" terminals No. 4 (Red wire) and No. 20 (Gray/Yellow wire). Repair as necessary. If PCM connections are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  5. Check HO2S B1 S1 Red wire and Gray/Yellow wire for opens or shorts. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair wiring or replace HO2S B1 S1 as necessary. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If HO2S B1 S1 Red wire and Gray/Yellow wire check okay, go to next step.
  6. Check fuel injector circuit. See «CIRCUIT TEST B-1: FUEL INJECTOR CIRCUIT INSPECTION»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-basic-diagnostic-procedures) in BASIC DIAGNOSTIC PROCEDURES article. Repair as necessary. If fuel injector circuit checks okay, go to next step.
  7. Measure resistance of fuel injectors on cylinders No. 1, 3 and 5. See INJECTOR RESISTANCE in SERVICE & ADJUSTMENTS article. Replace injector(s) as necessary. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If injector resistance is within specification, go to next step.
  8. Perform fuel pressure test. See «FUEL SYSTEM»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-basic-diagnostic-procedures__fuel-system) in BASIC DIAGNOSTIC PROCEDURES article. Repair as necessary. If fuel pressure is within specification, replace HO2S B1 S1. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system. If DTC P0132 resets, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC P0133: HEATED OXYGEN SENSOR (HO2S) SLOW RESPONSE BANK NO. 1 SENSOR NO. 1 (B1 S1)

Note. Before replacing HO2S B1 S1, inspect sensor for contamination. If contamination is present, determine cause and repair before installing a new HO2S B1 S1.

DTC is set when time for HO2S B1 S1 to change from lean to rich or from rich to lean takes longer than 5 seconds. MIL is illuminated when Power Control Module (PCM) detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. HO2S B1 S1 or circuit malfunction.
  2. PCM malfunction.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Ensure DTC P0135 is not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle at speeds of 50-60 MPH with engine speed at 2500-3000 RPM for one minute. Stop vehicle. Check for DTC P0133. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.

Check HO2S B1 S1 Red wire and Gray/Yellow wire for opens or shorts. See WIRING DIAGRAMS article. Repair wiring or replace HO2S B1 S1 as necessary. See REMOVAL, OVERHAUL & INSTALLATION article. If HO2S B1 S1 Red wire and Gray/Yellow wire check okay, replace HO2S B1 S1. See REMOVAL, OVERHAUL & INSTALLATION article. If trouble returns, replace PCM. See REMOVAL, OVERHAUL & INSTALLATION article. Retest system.

DTC is set when Power Control Module (PCM) detects HO2S B1 S1 voltage input is lower than .5 volts. MIL is illuminated when PCM detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. HO2S B1 S1 or circuit malfunction.
  2. Fuel injector malfunction.
  3. Fuel pressure control system malfunction.
  4. PCM malfunction.
  5. Low fuel level.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Ensure DTCs P0101, P0102, P0103, P0116, P0117, P0118 and P0135 are not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle at speeds of 40-50 MPH with throttle steady for 2 minutes. Stop vehicle. Check for DTC P0134. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. Connect scan tool to Data Link Connector (DLC). Drive vehicle for at least 2 minutes at 2000 RPM or greater with engine coolant at 158°F (70°C) or greater. Observe OXYGEN SENSOR B1 S1 parameter on scan tool. Reading should vary above and below .5 volt. If voltage is as specified, check for an intermittent problem. See «TROUBLE SHOOTING - NO CODES»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes) article. If voltage is not as specified, go to next step.
  2. Remove PCM cover, located below right side of instrument panel. Connect DVOM (backprobe) between PCM 26-pin connector "B" terminals No. 4 (Red wire) and No. 20 (Gray/Yellow wire). Start engine. Observe voltage while sharply increasing engine RPM and returning to idle several times. If reading reaches .5 volt or more, go to next step. If reading does not reach .5 volt, go to step 4 .
  3. Check for poor connection at PCM 26-pin connector "B" terminals No. 4 (Red wire) and No. 20 (Gray/Yellow wire). Repair as necessary. If PCM connections are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  4. Check HO2S B1 S1 Red wire and Gray/Yellow wire for opens or shorts. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair wiring or replace HO2S B1 S1 as necessary. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If HO2S B1 S1 Red wire and Gray/Yellow wire check okay, go to next step.
  5. Check fuel injector circuit. See «CIRCUIT TEST B-1: FUEL INJECTOR CIRCUIT INSPECTION»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-basic-diagnostic-procedures) in BASIC DIAGNOSTIC PROCEDURES article. Repair as necessary. If fuel injector circuit checks okay, go to next step.
  6. Measure resistance of fuel injectors on cylinders No. 1, 3 and 5. See INJECTOR RESISTANCE in SERVICE & ADJUSTMENTS article. Replace injector(s) as necessary. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If injector resistance is within specification, go to next step.
  7. Perform fuel pressure test. See «FUEL SYSTEM»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-basic-diagnostic-procedures__fuel-system) in BASIC DIAGNOSTIC PROCEDURES article. Repair as necessary. If fuel pressure is within specification, replace HO2S B1 S1. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system. If DTC P0134 resets, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC P0135: HEATED OXYGEN SENSOR (HO2S) NO. 1 HEATER CIRCUIT MALFUNCTION BANK NO. 1 SENSOR NO. 1 (B1 S1)

Note. Before replacing HO2S B1 S1, inspect sensor for contamination. If contamination is present, determine cause and repair before installing a new HO2S B1 S1.

DTC is set when Power Control Module (PCM) detects HO2S B1 S1 heater circuit voltage input is higher or lower than predetermined. MIL is illuminated when PCM detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. HO2S B1 S1 or circuit malfunction.
  2. PCM malfunction.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Ensure DTC P0135 is not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle at speeds of 35 MPH or more with throttle steady for 5 minutes. Stop vehicle and allow engine to idle for one minute. Check for DTC P0135. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. Turn ignition off. Disconnect HO2S 4-pin heater relay harness connector, located underhood on left fenderwell. (Scheme 18) Using an ohmmeter, measure resistance between HO2S 4-pin heater relay harness connector terminal No. 2 (Blue wire) and PCM 26-pin connector "B" terminal No. 6 (Gray wire). If resistance is 5-7 ohms at approximately 68°F (20°C), go to next step. If resistance is not 5-7 ohms at approximately 68°F (20°C), check for open in Blue wire between HO2S heater relay and HO2S B1 S1. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. If Blue wire is okay, check for open in Gray wire between HO2S B1 S1. and PCM. Repair as necessary. If Blue and Gray wires are okay, replace HO2S B1 S1. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  2. Turn ignition on. Using DVOM, measure voltage between ground and HO2S heater relay harness connector terminal No. 1 (Blue/White wire). Measure voltage between ground and HO2S heater relay harness connector terminal No. 3 (Black/White wire). If 10-14 volts exists at both terminals, go to next step. If 10-14 volts does not exist at both terminals, check for blown HO2S fuse No. 18 (15-amp) or IG METER fuse No. 21 (20-amp) in instrument panel fuse block. Replace blown fuse(s) as necessary and check for shorted circuit. If fuses are okay, check Black/White wire and Blue/White wire for an open. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary. Retest system.
  3. Turn ignition off. Connect HO2S heater relay. Turn ignition on. Remove PCM cover, located below right side of instrument panel. Using DVOM, measure voltage (backprobe) between ground and PCM 26-pin connector "B" terminal No. 6 (Gray wire). If 10-14 volts does not exist, go to next step. If 10-14 volts exists, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  4. Check for short to ground in Gray wire between HO2S B1 S1 and PCM. If Gray wire is okay, check for faulty HO2S relay. If HO2S relay checks okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

Scheme 18

Scheme 18
Scheme 18

DTC P0136: HEATED OXYGEN SENSOR (HO2S) CIRCUIT VOLTAGE HIGH BANK NO. 1 SENSOR NO. 2 (B1 S2)

Note. Before replacing HO2S B1 S2, inspect sensor for contamination. If contamination is present, determine cause and repair before installing a new HO2S B1 S2.

DTC is set when Power Control Module (PCM) detects maximum HO2S B1 S2 voltage input is more than 0.25 volts for 4 seconds when fuel is cut, less than 0.35 volts for 8 minutes, or more than 2 volts for 20 seconds. MIL is illuminated when PCM detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. HO2S B1 S2 or circuit malfunction.
  2. Fuel injector malfunction.
  3. Fuel pressure control system malfunction.
  4. PCM malfunction.
  5. Low fuel level.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Ensure DTCs P0111, P0112, P0113, P0335, P0461, P0463, P1450 and P1451 are not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle at speeds of 35 MPH or more with throttle steady for 5 minutes. Increase vehicle speed to 50-60 MPH and engine speed to 2500-3000 RPM with throttle steady for one minute. Release accelerator pedal and allow vehicle to coast (with vehicle in gear). Stop vehicle. Check for DTC P0136. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. Turn ignition off. Connect scan tool to Data Link Connector (DLC). Drive vehicle for at least 5 minutes at 35 MPH or greater with engine coolant temperature at 158°F (70°C) or greater. Observe OXYGEN SENSOR B1 S2 parameter on scan tool while sharply increasing engine RPM and returning to idle several times. If reading does not vary above and below .3 volt, go to next step. If reading varies above and below .3 volt, check for an intermittent problem. See «TROUBLE SHOOTING - NO CODES»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes) article. If all checks are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article.
  2. Check HO2S B1 S2 Red/Black wire and Gray/Yellow wire for opens or shorts. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair wiring or replace HO2S B1 S2 as necessary. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If HO2S B1 S2 Red/Black wire and Gray/Yellow wire check okay, go to next step.
  3. Check fuel injector circuit. See «CIRCUIT TEST B-1: FUEL INJECTOR CIRCUIT INSPECTION»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-basic-diagnostic-procedures) in BASIC DIAGNOSTIC PROCEDURES article. Repair as necessary. If fuel injector circuit checks okay, go to next step.
  4. Measure resistance of fuel injectors on cylinders No. 1, 3 and 5. See INJECTOR RESISTANCE in SERVICE & ADJUSTMENTS article. Replace injector(s) as necessary. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If injector resistance is within specification, go to next step.
  5. Perform fuel pressure test. See «FUEL SYSTEM»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-basic-diagnostic-procedures__fuel-system) in BASIC DIAGNOSTIC PROCEDURES article. Repair as necessary. If fuel pressure is within specification, replace HO2S B1 S2. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system. If DTC P0136 resets, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC P0141: HEATED OXYGEN SENSOR (HO2S) HEATER CIRCUIT MALFUNCTION BANK NO. 1 SENSOR NO. 2 (B1 S2)

Note. Before replacing HO2S B1 S2, inspect sensor for contamination. If contamination is present, determine cause and repair before installing a new HO2S B1 S2.

DTC is set when Power Control Module (PCM) detects HO2S B1 S2 heater circuit voltage input higher or lower than predetermined. MIL is illuminated when PCM detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. HO2S B1 S2 malfunction.
  2. PCM malfunction.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle at speeds of 35 MPH or more with throttle steady for 5 minutes. Stop vehicle and allow engine to idle for one minute. Check for DTC P0141. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. Turn ignition off. Disconnect HO2S 4-pin heater relay harness connector, located underhood on left fenderwell. (Scheme 18) Using an ohmmeter, measure resistance between HO2S 4-pin heater relay harness connector terminal No. 2 (Blue wire) and PCM 26-pin connector "B" terminal No. 17 (White/Black wire). If resistance is 5-7 ohms at approximately 68°F (20°C), go to next step. If resistance is not 5-7 ohms at approximately 68°F (20°C), check for open in Blue wire between HO2S heater relay and HO2S B1 S2. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. If Blue wire is okay, check for open in White/Black wire between HO2S B1 S2 and PCM. Repair as necessary. If Blue and White/Black wires are okay, replace HO2S B1 S2. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  2. Turn ignition on. Using DVOM, measure voltage between ground and HO2S heater relay harness connector terminal No. 1 (Blue/White wire). Measure voltage between ground and HO2S heater relay harness connector terminal No. 3 (Black/White wire). If 10-14 volts exists at both terminals, go to next step. If 10-14 volts does not exist at both terminals, check for blown HO2S fuse No. 18 (15-amp) or IG METER fuse No. 21 (20-amp) in instrument panel fuse block. Replace blown fuse(s) as necessary and check for shorted circuit. If fuses are okay, check Black/White wire and Blue/White wire for an open. Repair as necessary. Retest system.
  3. Turn ignition off. Connect HO2S heater relay. Turn ignition on. Remove PCM cover, located below right side of instrument panel. Using DVOM, measure voltage (backprobe) between ground and PCM 26-pin connector "B" terminal No. 17 (White/Black wire). If 10-14 volts exists, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system. If 10-14 volts does not exist, go to next step.
  4. Check for short to ground in White/Black wire between HO2S B1 S2 and PCM. If White/Black wire is okay, check for faulty HO2S relay. If HO2S relay checks okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC P0151: HEATED OXYGEN SENSOR (HO2S) CIRCUIT LOW VOLTAGE BANK NO. 2 SENSOR NO. 1 (B2 S1)

Note. Before replacing HO2S B2 S1, inspect sensor for contamination. If contamination is present, determine cause and repair before installing a new HO2S B2 S1.

DTC is set when HO2S B2 S1 maximum output voltage is 0.4 volts or less. MIL is illuminated when Power Control Module (PCM) detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. HO2S B2 S1 malfunction.
  2. Fuel injector malfunction.
  3. Fuel pressure control system malfunction.
  4. PCM malfunction.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle with engine speed at 2000-3000 RPM with throttle steady for one minute. Stop vehicle. Check for DTC P0151. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. Connect scan tool to Data Link Connector (DLC). Drive vehicle for at least 2 minutes at 2000 RPM or greater with engine coolant at 158°F (70°C) or greater. Observe OXYGEN SENSOR B2 S1 parameter on scan tool. If more than .4 volt is displayed, go to next step. If less than .4 volt is displayed, check for an intermittent problem. See «TROUBLE SHOOTING - NO CODES»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes) article. If all checks are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  2. Remove PCM cover, located below right side of instrument panel. Connect DVOM (backprobe) between PCM 26-pin connector "B" terminals No. 15 (Red/Blue wire) and No. 20 (Gray/Yellow wire). Start engine. Observe voltage while sharply increasing engine RPM and returning to idle. If more than .1 volt exists when fuel is cut, go to next step. If less than .1 volt exists when fuel is cut, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  3. Check HO2S B2 S1 Red/Blue wire and Gray/Yellow wire for opens or shorts. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair wiring or replace HO2S B2 S1 as necessary. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If HO2S B2 S1 Red/Blue wire and Gray/Yellow wire check okay, go to next step.
  4. Check fuel injector circuit. See «CIRCUIT TEST B-1: FUEL INJECTOR CIRCUIT INSPECTION»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-basic-diagnostic-procedures) in BASIC DIAGNOSTIC PROCEDURES article. Repair as necessary. If fuel injector circuit checks okay, go to next step.
  5. Measure resistance of fuel injectors on cylinders No. 2, 4 and 6. See «INJECTOR RESISTANCE»(/suzuki/grand-vitara/i-1997-2001/remont/specifications/#engine-controls-service-adjustment-specifications__injector-resistance) in SERVICE & ADJUSTMENTS SPECIFICATIONS article. Replace injector(s) as necessary. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If injector resistance is within specification, go to next step.
  6. Perform fuel pressure test. See «FUEL SYSTEM»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-basic-diagnostic-procedures__fuel-system) in BASIC DIAGNOSTIC PROCEDURES article. Repair as necessary. If fuel pressure is within specification, go to next step.
  7. Replace HO2S B2 S1. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system. If DTC P0151 resets, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC P0152: HEATED OXYGEN SENSOR (HO2S) CIRCUIT HIGH VOLTAGE BANK NO. 2 SENSOR NO. 1 (B2 S1)

Note. Before replacing HO2S B2 S1, inspect sensor for contamination. If contamination is present, determine cause and repair before installing a new HO2S B2 S1.

DTC is set when HO2S B2 S1 output voltage is 0.6-1.2 volts. MIL is illuminated when Power Control Module (PCM) detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. HO2S B2 S1 malfunction.
  2. PCM malfunction.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Ensure DTC P0135 is not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle with engine speed at 2000-3000 RPM with throttle steady for one minute. Stop vehicle. Check for DTC P0152. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Observe OXYGEN SENSOR B2 S1 parameter on scan tool. If one volt or more exists, go to next step. If less than one volt exists, go to step 3 .
  2. Check Red/Blue wire between PCM and HO2S B2 S1 for short to power. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary. If Red/Blue wire is okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  3. Remove PCM cover, located below right side of instrument panel. Connect DVOM (backprobe) between PCM 26-pin connector "B" terminals No. 15 (Red/Blue wire) and No. 20 (Gray/Yellow wire). Start engine. Observe voltage while sharply increasing engine RPM and returning to idle several times. If reading varies 0-1 volt, go to next step. If reading does not vary 0-1 volt, go to step 5 .
  4. Check for poor connection at PCM 26-pin connector "B" terminals No. 15 (Red/Blue wire) and No. 20 (Gray/Yellow wire). Repair as necessary. If PCM connections are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  5. Check HO2S B2 S1 Red/Blue wire and Gray/Yellow wire for opens or shorts. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair wiring or replace HO2S B2 S1 as necessary. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If HO2S B2 S1 Red/Blue wire and Gray/Yellow wire check okay, go to next step.
  6. Check fuel injector circuit. See «CIRCUIT TEST B-1: FUEL INJECTOR CIRCUIT INSPECTION»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-basic-diagnostic-procedures) in BASIC DIAGNOSTIC PROCEDURES article. Repair as necessary. If fuel injector circuit checks okay, go to next step.
  7. Measure resistance of fuel injectors on cylinders No. 2, 4 and 6. See INJECTOR RESISTANCE in SERVICE & ADJUSTMENTS article. Replace injector(s) as necessary. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If injector resistance is within specification, go to next step.
  8. Perform fuel pressure test. See «FUEL SYSTEM»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-basic-diagnostic-procedures__fuel-system) in BASIC DIAGNOSTIC PROCEDURES article. Repair as necessary. If fuel pressure is within specification, go to next step.
  9. Replace HO2S B2 S1. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system. If DTC P0152 resets, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC P0153: HEATED OXYGEN SENSOR (HO2S) CIRCUIT SLOW RESPONSE BANK NO. 2 SENSOR NO. 1 (B2 S1)

Note. Before replacing HO2S B2 S1, inspect sensor for contamination. If contamination is present, determine cause and repair before installing a new HO2S B2 S1.

DTC is set when time for HO2S B2 S1 to change from lean to rich or from rich to lean takes longer than 5 seconds. MIL is illuminated when Power Control Module (PCM) detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. HO2S B2 S1 malfunction.
  2. PCM malfunction.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Ensure DTC P0135 is not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle at speeds of 50-60 MPH with engine speed at 2500-3000 RPM with throttle steady for one minute. Stop vehicle. Check for DTC P0153. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.

Check HO2S B2 S1 Red/Blue wire and Gray/Yellow wire for opens or shorts. See WIRING DIAGRAMS article. Repair wiring or replace HO2S B2 S1 as necessary. See REMOVAL, OVERHAUL & INSTALLATION article. If HO2S B2 S1 Red/Blue wire and Gray/Yellow wire check okay, replace HO2S B2 S1. See REMOVAL, OVERHAUL & INSTALLATION article. If trouble returns, replace PCM. See REMOVAL, OVERHAUL & INSTALLATION article. Retest system.

DTC is set when Power Control Module (PCM) detects HO2S B2 S1 voltage input is lower than .5 volts. MIL is illuminated when PCM detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. HO2S B2 S1 malfunction.
  2. Fuel injector malfunction.
  3. Fuel pressure control system malfunction.
  4. PCM malfunction.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Ensure DTCs P0101, P0102, P0103, P0116, P0117, P0118 and P0135 are not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle at speeds of 40-50 MPH with throttle steady for 2 minutes. Stop vehicle. Check for DTC P0154. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. Turn ignition off. Connect scan tool to Data Link Connector (DLC). Drive vehicle for at least one minute at 2000 RPM or greater with engine coolant at 158°F (70°C) or greater. Observe OXYGEN SENSOR B2 S1 parameter on scan tool. Reading should vary above and below .5 volt. If voltage is as specified, check for an intermittent problem. See «TROUBLE SHOOTING - NO CODES»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes) article. If all checks are good, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system. If voltage is not as specified, go to next step.
  2. Remove PCM cover, located below right side of instrument panel. Connect DVOM (backprobe) between PCM 26-pin connector "B" terminals No. 15 (Red/Blue wire) and No. 20 (Gray/Yellow wire). Start engine. Observe voltage while sharply increasing engine RPM and returning to idle several times. If reading reaches .5 volt or more, go to next step. If reading does not reach .5 volt, go to step 4 .
  3. Check for poor connection at PCM 26-pin connector "B" terminals No. 15 (Red/Blue wire) and No. 20 (Gray/Yellow wire). Repair as necessary. If PCM connections are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  4. Check HO2S B2 S1 Red/Blue wire and Gray/Yellow wire for opens or shorts. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair wiring or replace HO2S B2 S1 as necessary. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If HO2S B2 S1 Red/Blue wire and Gray/Yellow wire check okay, go to next step.
  5. Check fuel injector circuit. See «CIRCUIT TEST B-1: FUEL INJECTOR CIRCUIT INSPECTION»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-basic-diagnostic-procedures) in BASIC DIAGNOSTIC PROCEDURES article. Repair as necessary. If fuel injector circuit checks okay, go to next step.
  6. Measure resistance of fuel injectors on cylinders No. 2, 4 and 6. See INJECTOR RESISTANCE in SERVICE & ADJUSTMENTS article. Replace injector(s) as necessary. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If injector resistance is within specification, go to next step.
  7. Perform fuel pressure test. See «FUEL SYSTEM»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-basic-diagnostic-procedures__fuel-system) in BASIC DIAGNOSTIC PROCEDURES article. Repair as necessary. If fuel pressure is within specification, replace HO2S B2 S1. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system. If DTC P0154 resets, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC P0155: HEATED OXYGEN SENSOR (HO2S) HEATER CIRCUIT MALFUNCTION BANK NO. 2 SENSOR NO. 1 (B2 S1)

Note. Before replacing HO2S B2 S1, inspect sensor for contamination. If contamination is present, determine cause and repair before installing a new HO2S B2 S1.

DTC is set when Power Control Module (PCM) detects HO2S B2 S1 heater circuit voltage input higher or lower than predetermined. MIL is illuminated when PCM detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. HO2S B2 S1 malfunction.
  2. PCM malfunction.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle at speeds of 35 MPH or more with throttle steady for 5 minutes. Stop vehicle and allow engine to idle for one minute. Check for DTC P0155. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. Turn ignition off. Disconnect HO2S 4-pin heater relay harness connector, located underhood on left fenderwell. (Scheme 18) Using an ohmmeter, measure resistance between HO2S 4-pin heater relay harness connector terminal No. 2 (Blue wire) and PCM 26-pin connector "B" terminal No. 5 (Black/Red wire). If resistance is 5-7 ohms at approximately 68°F (20°C), go to step 3. If resistance is not 5-7 ohms at approximately 68°F (20°C), go to next step.
  2. Check for open in Blue wire between HO2S heater relay and HO2S B2 S1. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. If Blue wire is okay, check for open in Black/Red wire between HO2S B2 S1 and PCM. Repair as necessary. If Blue and Black/Red wires are okay, replace HO2S B2 S1. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  3. Turn ignition on. Using DVOM, measure voltage between ground and HO2S heater relay harness connector terminal No. 1 (Blue/White wire). Measure voltage between ground and HO2S heater relay harness connector terminal No. 3 (Black/White wire). If 10-14 volts exists at both terminals, go to step 5. If 10-14 volts does not exist at both terminals, go to next step.
  4. Check for blown HO2S fuse No. 18 (15-amp) or IG METER fuse No. 21 (20-amp) in instrument panel fuse block. Replace blown fuse(s) as necessary and check for shorted circuit. If fuses are okay, check Black/White wire and Blue/White wire for an open. Repair as necessary. Retest system.
  5. Turn ignition off. Connect HO2S heater relay. Turn ignition on. Remove PCM cover, located below right side of instrument panel. Using DVOM, measure voltage (backprobe) between ground and PCM 26-pin connector "B" terminal No. 5 (Black/Red wire). If 10-14 volts exists, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system. If 10-14 volts does not exist, go to next step.
  6. Check for short to ground in Black/Red wire between HO2S B2 S1 and PCM. If Black/Red wire is okay, check for faulty HO2S relay. If HO2S relay checks okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC P0156: HEATED OXYGEN SENSOR (HO2S) CIRCUIT HIGH VOLTAGE BANK NO. 2 SENSOR NO. 2 (B2 S2)

Note. Before replacing HO2S B2 S2, inspect sensor for contamination. If contamination is present, determine cause and repair before installing a new HO2S B2 S2.

DTC is set when Power Control Module (PCM) detects maximum HO2S B2 S2 voltage input is more than 0.25 volts for 4 seconds when fuel is cut, less than 0.35 volts for 8 minutes, or more than 2 volts for 20 seconds. MIL is illuminated when PCM detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. HO2S B2 S2 malfunction.
  2. Fuel injector malfunction.
  3. Fuel pressure control system malfunction.
  4. PCM malfunction.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Ensure DTCs P0111, P0112, P0113, P0335, P0461, P0463,P1450 and P1451 are not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle at speeds of 35 MPH or more with throttle steady for 5 minutes. Increase vehicle speed to 50-60 MPH and engine speed to 2500-3000 RPM with throttle steady for one minute. Release accelerator pedal and allow vehicle to coast (with vehicle in gear). Stop vehicle. Check for DTC P0156. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Observe OXYGEN SENSOR B2 S2 parameter on scan tool. If reading does not vary to above and below .3 volt, go to next step. If reading varies to above and below .3 volt, check for an intermittent problem. See «TROUBLE SHOOTING - NO CODES»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes) article. If all checks are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article.
  2. Check HO2S B2 S2 Red/Yellow wire and Gray/Yellow wire for opens or shorts. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair wiring or replace HO2S B2 S2 as necessary. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If HO2S B2 S2 Red/Yellow wire and Gray/Yellow wire check okay, go to next step.
  3. Check fuel injector circuit. See «CIRCUIT TEST B-1: FUEL INJECTOR CIRCUIT INSPECTION»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-basic-diagnostic-procedures) in BASIC DIAGNOSTIC PROCEDURES article. Repair as necessary. If fuel injector circuit checks okay, go to next step.
  4. Measure resistance of fuel injectors on cylinders No. 2, 4 and 6. See INJECTOR RESISTANCE in SERVICE & ADJUSTMENTS article. Replace injector(s) as necessary. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If injector resistance is within specification, go to next step.
  5. Perform fuel pressure test. See «FUEL SYSTEM»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-basic-diagnostic-procedures__fuel-system) in BASIC DIAGNOSTIC PROCEDURES article. Repair as necessary. If fuel pressure is within specification, go to next step.
  6. Replace HO2S B2 S2. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system. If DTC P0156 resets, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC P0161: HEATED OXYGEN SENSOR (HO2S) HEATER CIRCUIT MALFUNCTION BANK NO. 2 SENSOR NO. 2 (B2 S2)

Note. Before replacing HO2S B2 S2, inspect sensor for contamination. If contamination is present, determine cause and repair before installing a new HO2S B2 S2.

DTC is set when Power Control Module (PCM) detects HO2S B2 S2 heater circuit voltage input higher or lower than predetermined. MIL is illuminated when PCM detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. HO2S B2 S2 malfunction.
  2. PCM malfunction.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle at speeds of 35 MPH or more with throttle steady for 5 minutes. Stop vehicle and allow engine to idle for one minute. Check for DTC P0161. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. Turn ignition off. Disconnect HO2S 4-pin heater relay harness connector, located underhood on left fenderwell. (Scheme 18) Using an ohmmeter, measure resistance between HO2S 4-pin heater relay harness connector terminal No. 2 (Blue wire) and PCM 26-pin connector "B" terminal No. 16 (Pink/White wire). If resistance is 5-7 ohms at approximately 68°F (20°C), go to step 3. If resistance is not 5-7 ohms at approximately 68°F (20°C), go to next step.
  2. Check for open in Blue wire between HO2S heater relay and HO2S B2 S2. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. If Blue wire is okay, check for open in Pink/White wire between HO2S B2 S2 and PCM. Repair as necessary. If Blue and Pink/White wires are okay, replace HO2S B2 S2. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  3. Turn ignition on. Using DVOM, measure voltage between ground and HO2S heater relay harness connector terminal No. 1 (Blue/White wire). Measure voltage between ground and HO2S heater relay harness connector terminal No. 3 (Black/White wire). If 10-14 volts exists at both terminals, go to next step. If 10-14 volts does not exist at both terminals, check for blown HO2S fuse No. 18 (15-amp) or IG METER fuse No. 21 (20-amp) in instrument panel fuse block. Replace blown fuse(s) as necessary and check for shorted circuit. If fuses are okay, check Black/White wire and Blue/White wire for an open. Repair as necessary. Retest system.
  4. Turn ignition off. Connect HO2S heater relay. Turn ignition on. Remove PCM cover, located below right side of instrument panel. Using DVOM, measure voltage (backprobe) between ground and PCM 26-pin connector "B" terminal No. 16 (Pink/White wire). If 10-14 volts exists, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system. If 10-14 volts does not exist, go to next step.
  5. Check for short to ground in Pink/White wire between HO2S B2 S2 and PCM. If Pink/White wire is okay, check for faulty HO2S relay. If HO2S relay checks okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC P0171 is set when Power Control Module (PCM) detects that total fuel trim of bank No. 1 is more than 33 percent. DTC P0172 is set when PCM detects that total fuel trim of bank No. 1 is less than -33 percent. MIL is illuminated when PCM detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. Intake system vacuum leaks.
  2. Exhaust system leaks.
  3. Incorrect fuel pressure.
  4. Fuel injector malfunction.
  5. HO2S B1 S1 malfunction.
  6. Mass Air Flow (MAF) sensor or circuit malfunction.
  7. Engine Coolant Temperature (ECT) sensor or circuit malfunction.
  8. Fuel level sensor or circuit malfunction.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Ensure DTCs P0131, P0132, P0133 and P0134 are not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle under conditions during which DTC was originally set or under freeze frame data conditions for 5 minutes. Stop vehicle and check for DTC P0171 or P0172. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. If other DTCs are set, go to those first. Check intake and exhaust system for any leakage. Repair as necessary. If intake and exhaust system check okay, go to next step.
  2. Check fuel pressure. See «FUEL PRESSURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-basic-diagnostic-procedures) in BASIC DIAGNOSTIC PROCEDURES article. If fuel pressure is within specifications, go to next step. If fuel pressure is not as specified, repair as necessary. Retest system.
  3. Measure resistance of fuel injectors on cylinders No. 1, 3 and 5. See INJECTOR RESISTANCE in SERVICE & ADJUSTMENTS article. Replace injector(s) as necessary. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If injector resistance is within specification, go to next step.
  4. Check fuel injector circuit. See «CIRCUIT TEST B-1: FUEL INJECTOR CIRCUIT INSPECTION»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-basic-diagnostic-procedures) in BASIC DIAGNOSTIC PROCEDURES article. Repair as necessary. If fuel injector circuit checks okay, go to next step.
  5. Check fuel level sensor. See appropriate INSTRUMENT PANELS article in ELECTRICAL. If problem exists, repair as necessary. Retest system. If fuel level sensor is okay, go to next step.
  6. Check MAF sensor circuit performance. See SYSTEM & COMPONENT TESTING article. If problem exists, repair as necessary. Retest system. If MAF sensor circuit is okay, go to next step.
  7. Check ECT sensor circuit performance. See SYSTEM & COMPONENT TESTING article. If problem exists, repair as necessary. Retest system. If ECT sensor circuit is okay, go to next step.
  8. Check HO2S B1 S1 circuit performance. See step 1 of «DTC P0134: HEATED OXYGEN SENSOR (HO2S) NO ACTIVITY DETECTED BANK NO. 1 SENSOR NO. 1 (B1 S1)»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics) . If problem exists, repair as necessary. If HO2S B1 S1 circuit is okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC P0174 is set when Power Control Module (PCM) detects that total fuel trim of bank No. 2 is more than 33 percent. DTC P0175 is set when PCM detects that total fuel trim of bank No. 2 is less than -33 percent. MIL is illuminated when PCM detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. Intake system vacuum leaks.
  2. Exhaust system leaks.
  3. Incorrect fuel pressure.
  4. Fuel injector malfunction.
  5. HO2S B2 S1 malfunction.
  6. Mass Air Flow (MAF) sensor or circuit malfunction.
  7. Engine Coolant Temperature (ECT) sensor or circuit malfunction.
  8. Fuel level sensor or circuit malfunction.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Ensure DTCs P0131, P0132, P0133 and P0134 are not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle under conditions during which DTC was originally set or under freeze frame data conditions for 5 minutes. Stop vehicle and check for DTC P0174 or P0175. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. If other DTCs are set, go to those first. Check intake and exhaust system for any leakage. Repair as necessary. If intake and exhaust system check okay, go to next step.
  2. Check fuel pressure. See «FUEL PRESSURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-basic-diagnostic-procedures) in BASIC DIAGNOSTIC PROCEDURES article. If fuel pressure is within specifications, go to next step. If fuel pressure is not as specified, repair as necessary. Retest system.
  3. Measure resistance of fuel injectors on cylinders No. 2, 4 and 6. See INJECTOR RESISTANCE in SERVICE & ADJUSTMENTS article. Replace injector(s) as necessary. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If injector resistance is within specification, go to next step.
  4. Check fuel injector circuit. See «CIRCUIT TEST B-1: FUEL INJECTOR CIRCUIT INSPECTION»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-basic-diagnostic-procedures) in BASIC DIAGNOSTIC PROCEDURES article. Repair as necessary. If fuel injector circuit checks okay, go to next step.
  5. Check fuel level sensor. See appropriate INSTRUMENT PANELS article in ELECTRICAL. If problem exists, repair as necessary. Retest system. If fuel level sensor is okay, go to next step.
  6. Check MAF sensor circuit performance. See SYSTEM & COMPONENT TESTING article. If problem exists, repair as necessary. Retest system. If MAF sensor circuit is okay, go to next step.
  7. Check ECT sensor circuit performance. See SYSTEM & COMPONENT TESTING article. If problem exists, repair as necessary. Retest system. If ECT sensor circuit is okay, go to next step.
  8. Check HO2S B2 S1 circuit. See step 1 of «DTC P0154: HEATED OXYGEN SENSOR (HO2S) NO ACTIVITY DETECTED BANK NO. 2 SENSOR NO. 1 (B2 S1)»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics) . If problem exists, repair as necessary. If HO2S B2 S1 sensor circuit is okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

Power Control Module (PCM) monitors Crankshaft Position (CKP) sensor input signal interval time. It detects a misfire in a specific cylinder by calculating change of CKP interval time for each cylinder. While engine is operating, PCM counts number of misfires that occurred during 200 crankshaft revolutions and during 1000 crankshaft revolutions in order to calculate a misfire ratio for each crankshaft revolution. If misfire ratio exceeds a preprogrammed criteria during 200 crankshaft revolutions, PCM determines that a misfire has occurred which can damage the catalytic converter, will set a DTC and will flash MIL. If misfire ratio exceeds a preprogrammed criteria during 1000 crankshaft revolutions, PCM will set a DTC and illuminate MIL when it detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. Secondary ignition system malfunction.
  2. Plugged or leaking fuel injector.
  3. Incorrect fuel pressure.
  4. EGR system malfunction.
  5. Fuel level sensor or circuit malfunction.
  6. Intake system vacuum leaks.
  7. Incorrect engine compression.
  8. Incorrect valve clearance.
  9. Incorrect valve timing.
  10. Low fuel level.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Ensure DTCs P0335 and P0340 are not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Drive vehicle under conditions during which DTC was originally set or under freeze frame data conditions for 1 minute. Stop vehicle and check for DTC P0300, P0301, P0302, P0303, P0304, P0305 or P0306. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. Check ignition spark and spark plug at misfiring cylinder. See IGNITION CHECKS in BASIC DIAGNOSTIC PROCEDURES article. Repair as necessary. If a strong Blue spark is present at ignition wire and spark plug is okay, go to next step.
  2. Check fuel injector circuit. See «CIRCUIT TEST B-1: FUEL INJECTOR CIRCUIT INSPECTION»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-basic-diagnostic-procedures) in BASIC DIAGNOSTIC PROCEDURES article. Repair as necessary. If fuel injector circuit checks okay, go to next step.
  3. Using a mechanic's stethoscope, check each fuel injector for a clicking sound while cranking engine. If sound is not heard from all 6 injectors, go to the next step. If sound is heard from all 6 injectors, go to step 6 .
  4. Check inoperative fuel injector(s) harness and connections. Using a fuel injector tester (noid-light), check injector control signal at each harness connector. If injector control signal exists, go to next step. If injector control signal does not exist, check circuit and PCM. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary. Retest system.
  5. Measure resistance of fuel injectors. See INJECTOR RESISTANCE in SERVICE & ADJUSTMENTS article. Replace injector(s) as necessary. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If injector resistance is within specification, go to next step.
  6. Check fuel pressure. See «FUEL PRESSURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-basic-diagnostic-procedures) in BASIC DIAGNOSTIC PROCEDURES article. Repair as necessary. If fuel pressure is okay, go to next step.
  7. Check ignition timing. See «IGNITION TIMING»(/suzuki/grand-vitara/i-1997-2001/remont/adjustments/#engine-controls-on-vehicle-adjustments__ignition-timing) in ON VEHICLE ADJUSTMENTS article. Adjust if necessary. Retest system. If ignition timing is okay, go to next step.
  8. Check EGR system for proper operation. See «EXHAUST GAS RECIRCULATION (EGR)»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-system-component-testing) in EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM & COMPONENT TESTING article. Repair as necessary. If EGR operation is okay, go to next step.
  9. Check fuel level sensor. See appropriate INSTRUMENT PANELS article in ELECTRICAL. If problem exists, repair as necessary. Retest system. If fuel level sensor is okay, go to next step.
  10. Check engine mechanical condition. See appropriate article in ENGINES. If engine mechanical condition is okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC is set when Power Control Module (PCM) detects no CKP sensor signal input for 3 seconds with engine running. Possible causes are

  1. CKP sensor or circuit malfunction.
  2. PCM malfunction.

Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Ensure DTC P0340 is not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article. Start engine and allow it to idle for 10 seconds. Check for DTC P0335. See RETRIEVING DTCS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.

  1. Turn ignition off. Remove PCM cover, located below right side of instrument panel. Disconnect PCM 26-pin connector "B". Using DVOM, measure resistance between PCM 26-pin connector "B" terminals No. 2 (Orange/Black wire) and No. 3 (White/Blue wire). If resistance is 484-656 ohms, go to step 3. If resistance is not as specified, go to next step.
  2. Disconnect CKP sensor harness connector. Using an ohmmeter, measure resistance between CKP sensor terminals No. 1 and 2. (Scheme 19) Resistance should be 485-655 ohms. If resistance is as specified, repair open in White/Blue wire or Orange/Black wire. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. If resistance is not as specified, replace CKP sensor. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  3. Check CKP sensor installation and condition of teeth on crankshaft. Repair as necessary. If CKP sensor and crankshaft are okay, check for poor connections at PCM. Check for White/Blue wire or Orange/Black wire shorted to another circuit. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary. If PCM connections and circuit wiring are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

Scheme 19

Scheme 19
Scheme 19

DTC is set when Power Control Module (PCM) detects no CMP sensor input voltage for 5 seconds with engine start signal being inputted. DTC is also set when PCM detects less than 10 CMP sensor voltage pulses for every 2 Crankshaft Position (CKP) sensor pulses. Possible causes are

  1. CMP sensor or circuit malfunction.
  2. Engine start signal circuit malfunction.
  3. PCM malfunction.

Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Ensure DTCs P0335 is not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article. Crank engine for 8 seconds. Check for DTC P0340. See RETRIEVING DTCS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.

  1. Remove PCM cover, located below right side of instrument panel. Start engine. Using DVOM, measure voltage (backprobe) between ground and PCM 28-pin connector "D" terminal No. 26 (Black/Yellow wire). If 0-1 volt exists, leave DVOM connected, stop engine and go to next step. If 0-1 volt does not exist, repair short to power in Black/Yellow wire. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Retest system.
  2. With DVOM still connected between ground and PCM 28-pin connector "D" terminal No. 26 (Black/Yellow wire), observe voltage while cranking engine. If 6-14 volts does not exist, check for an open in Black/Yellow wire. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary. If Black/Yellow wire is okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If 6-14 volts exists, check for an intermittent problem. See «TROUBLE SHOOTING - NO CODES»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes) article. If all checks are good, go to next step.
  3. Turn ignition off. Disconnect CMP sensor harness connector. Turn ignition on. Using DVOM, measure voltage between CMP sensor harness connector terminals No. 1 (Gray/Yellow wire) and No. 2 (Blue/Black wire). If 10-14 volts exists, go to next step. If 10-14 volts does not exist, check for open or poor connection in Blue/Black wire or Gray/Yellow wire. Repair as necessary. Retest system.
  4. Turn ignition off. Reconnect CMP sensor harness connector. Disconnect harness connectors from ignition coil assembly and fuel injectors. Connect DVOM (backprobe) between PCM 26-pin connector "B" terminals No. 10 (Yellow/Blue wire) and No. 20 (Gray/Yellow wire). Turn ignition on. Observe voltage reading while slowly turning crankshaft 2 complete revolutions. Reading should toggle between 0-1 volt and 4-6 volts (6 times with 2 revolutions of crankshaft). If voltage is as specified, go to next step. If voltage is not as specified, check for open or short in Yellow/Blue wire between CMP sensor and PCM. Repair as necessary. If wiring is okay, check for faulty CMP sensor or PCM. Repair as necessary. Retest system.
  5. Connect DVOM (backprobe) between PCM 26-pin connector "B" terminals No. 9 (Yellow/Green wire) and No. 20 (Gray/Yellow wire). Turn ignition on. Observe voltage reading while slowly turning crankshaft. Reading should toggle between 0-1 volt and 4-6 volts. If voltage is as specified, go to next step. If voltage is not as specified, check for open or short in Yellow/Green wire between CMP sensor and PCM. Repair as necessary. If wiring is okay, check for faulty CMP sensor or PCM. Repair as necessary. Retest system.
  6. Check for poor connection at PCM connector "B" terminals No. 9 (Yellow/Green wire) and No. 10 (Yellow/Blue wire). Repair as necessary. If connections are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC is set when difference in intake manifold absolute pressure value when EGR valve is opened and when EGR valve is closed is less than predetermined. MIL is illuminated when Power Control Module (PCM) detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. EGR valve malfunction.
  2. EGR passage restricted.
  3. Manifold Absolute Pressure (MAP) sensor or circuit malfunction.
  4. PCM malfunction.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Ensure DTC P1408 is not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle at speeds of 30-40 MPH and engine speed of 2000-3000 RPM with throttle steady for 3 minutes. Stop vehicle. Check for DTC P0400. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. If using scan tool, check EGR system referring to EXHAUST GAS RECIRCULATION (EGR) under EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM & COMPONENT TESTING article. If scan tool is unavailable, go to next step.
  2. Turn ignition off. Disconnect EGR valve harness connector. Turn ignition on. Using DVOM, measure voltage between ground and EGR valve harness connector terminals No. 2 and No. 5 (Blue/Black wires). If 10-14 volts exists on both terminals, go to next step. If 10-14 volts does not exist on both terminals, repair open Blue/Black wire. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Retest system.
  3. Turn ignition off. Connect EGR valve harness connector. Remove PCM cover, located below right side of instrument panel. Disconnect PCM connectors. Connect one lead of ohmmeter to PCM 28-pin connector "D" terminal No. 20 (Blue/Black wire). While observing DVOM reading, connect other lead of ohmmeter to PCM 28-pin connector "D" terminals No. 4 (Light Green/White wire), No. 5 (Light Green wire), No. 16 (Light Green/Red wire) and No. 17 (Light Green/Yellow wire). Resistance should be 20-24 ohms at each terminal. If resistance is as specified, go to next step. If resistance is not as specified, go to step 5 .
  4. Check for a stuck or faulty EGR valve. Check for clogged EGR passage in intake manifold. Repair as necessary. If EGR valve and passage are okay, check MDP sensor. See SYSTEM & COMPONENT TESTING article. If MDP sensor checks okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  5. Check for open or short in Light Green wire, Light Green/White wire, Light Green/Red wire and Light Green/Yellow wire between EGR valve and PCM. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary. If wiring between EGR valve and PCM is okay, test EGR valve. See EXHAUST GAS RECIRCULATION (EGR) under EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM & COMPONENT TESTING article.

DTC is set when value from HO2S No. 2 becomes closer to value from HO2S No. 1 at either bank. MIL is illuminated when Power Control Module (PCM) detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. Catalytic converter malfunction.
  2. Exhaust system leak.
  3. HO2S No. 2 malfunction.
  4. PCM malfunction.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Ensure DTCs P0101, P0102, P0103, P0111, P0112, P0113, P0116, P0117, P0118, P0131, P0132, P0133, P0134, P0135, P0136, P0141, P0335, P0461, P0463, P0500, P1450 and P1451 are not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle at speeds of 35 MPH or more with throttle steady for 5 minutes. Increase vehicle speeds 50-60 MPH and engine speed to 2500-3000 RPM for one minute. Stop vehicle. Check for DTC P0420 or P0430. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. Visually inspect exhaust system for any leaks or damage. Repair as necessary. If exhaust system checks okay, check appropriate HO2S No. 2 wiring circuit. For DTC P0420, check for open or short in Red/Blue wire or Gray/Yellow wire between HO2S B1 S2 and PCM. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. For DTC P0430, check for open or short in Red/Yellow wire or Gray/Yellow wire between HO2S B2 S2 and PCM. Repair wiring or replace HO2S as necessary. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If HO2S wiring checks okay, go to next step.
  2. Replace HO2S No. 2 on appropriate bank of engine (bank 1 for DTC P0420; bank 2 for DTC P0430). See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system. If problem returns, replace appropriate warm-up Three Way Converter (TWC). For DTC P0420, replace warm-up TWC on bank one. For DTC P0430, replace warm-up TWC on bank two. Retest system. If problem returns, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC P0440: EVAPORATIVE (EVAP) CONTROL SYSTEM MALFUNCTION OR DTC P0455: EVAPORATIVE (EVAP) CONTROL SYSTEM LEAK DETECTED

WARNINGThis work must be performed in a well ventilated area away from any open flame.

Note. Ensure fuel filler cap is tightened securely and gasket is in good condition. Inspect vacuum hoses for kinks, loose connections and deterioration before testing EVAP system.

With engine running, Power Control Module (PCM) closes EVAP canister air valve and opens EVAP canister purge valve. If EVAP control system is okay, EVAP control system pressure detected by fuel pressure sensor is lowered. When EVAP control system pressure is lowered, PCM closes EVAP canister purge valve, leaving EVAP canister air valve closed. If EVAP system is okay, fuel tank pressure will increase to a predetermined level.

DTC P0440 is set when fuel tank pressure increase exceeds a predetermined value. MIL is illuminated when PCM detects malfunction during 2 consecutive drive cycles. DTC P0455 is set when fuel tank pressure change is less than predetermined. MIL is illuminated when PCM detects malfunction during first drive cycle. Possible causes are

  1. Missing, loose or malfunctioning fuel filler cap.
  2. Loose or plugged vacuum hose.
  3. Components mounted to fuel tank leaking in area of mounting.
  4. EVAP canister plugged.
  5. EVAP canister purge valve malfunction.
  6. EVAP canister air valve malfunction.
  7. Fuel tank pressure control valve malfunction.
  8. Fuel Tank Pressure (FTP) sensor or circuit malfunction.
  9. Fuel level sensor or circuit malfunction.
  10. PCM malfunction.

DTC Confirmation Test (P0440)

  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Ensure DTCs P0101, P0102, P0103, P0111, P0112, P0113, P0116, P0117, P0118, P0131, P0132, P0133, P0134, P0135, P0136, P0141, P0335, P0461, P0463, P0500, P1450 and P1451 are not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article. Start engine and allow it to reach normal operating temperature. Drive vehicle at speeds of 25 MPH or more with throttle steady for 15 minutes.
  2. Stop vehicle. Check for DTCs P0440. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article. If DTCs are not set, check completion status of evaporative system monitoring test in READINESS TESTS mode. If testing has not been completed, drive vehicle at speeds of 25 MPH or more with throttle steady for 15 minutes. Stop vehicle. Check for DTCs P0440. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.

DTC Confirmation Test (P0455)

  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle at speeds of 35 MPH or more with throttle steady for 10 minutes. Stop vehicle and allow it to idle for one minute. Check for DTCs P0455. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. Check evaporative canister purge valve and circuit operation. See «EVAP CANISTER PURGE VALVE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-system-component-testing) in SYSTEM & COMPONENT TESTING article. If canister purge valve operation is as specified, go to next step. If operation is not as specified, check for clogged vacuum passage. Clean or repair as necessary.
  2. Check evaporative canister air valve and circuit operation. See «FUEL EVAPORATION»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-system-component-testing) in SYSTEM & COMPONENT TESTING article. If evaporative canister air valve operation is as specified, go to next step. If operation is not as specified, repair as necessary.
  3. Check fuel tank pressure control valve operation. See «FUEL EVAPORATION»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-system-component-testing) in SYSTEM & COMPONENT TESTING article. If fuel tank pressure control valve operation is as specified, go to next step. If operation is not as specified, replace fuel tank pressure control valve. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  4. Check fuel tank pressure control solenoid valve and circuit operation. See «FUEL TANK PRESSURE CONTROL VALVE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-system-component-testing__fuel-tank-pressure-control-valve) in SYSTEM & COMPONENT TESTING article. If fuel tank pressure solenoid valve operation is as specified, go to next step. If operation is not as specified, repair as necessary and retest system.
  5. Check evaporative canister for damage or clogged passages. See «EVAP CANISTER»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-system-component-testing__evap-canister) in SYSTEM & COMPONENT TESTING article. If evaporative canister operation is as specified, go to next step. If operation is not as specified, replace evaporative canister. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  6. Inspect purge line, evaporative system components and fuel tank for leaks. See «FUEL EVAPORATION»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-system-component-testing) in SYSTEM & COMPONENT TESTING article. If any leaks are found, repair or replace system or components as necessary. If no leaks are found, go to next step.
  7. Check fuel tank pressure sensor operation. See «FUEL TANK PRESSURE SENSOR»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-system-component-testing__fuel-tank-pressure-sensor) in SYSTEM & COMPONENT TESTING article. If fuel tank pressure sensor operation is not as specified, replace fuel tank pressure sensor. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system. If operation is as specified, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC P0450: EVAPORATIVE (EVAP) CONTROL SYSTEM PRESSURE SENSOR MALFUNCTION

WARNINGThis work must be performed in a well ventilated area away from any open flame.

DTC is set when Power Control Module (PCM) detects Fuel Tank Pressure (FTP) sensor output voltage is less than 0.1 volt or more than 5 volts. MIL is illuminated when PCM detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. FTP sensor or circuit malfunction.
  2. PCM malfunction.

Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Ensure DTCs P1450 and P1451 are not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article. Start engine and allow it to idle for 10 seconds. Check for DTC P0450. See RETRIEVING DTCS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.

  1. Remove fuel filler cap. Remove PCM cover, located below right side of instrument panel. Connect DVOM (backprobe) between PCM 35-pin connector "A" terminals No. 20 (Brown/Red wire) and No. 32 (Gray/Yellow wire). Turn ignition on. If 2.0-2.5 volts exists, go to next step. If 2.0-2.5 volts does not exist, check fuel tank pressure sensor. See «FUEL EVAPORATION»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-system-component-testing) in SYSTEM & COMPONENT TESTING article. If fuel tank pressure sensor checks okay, go to step 3 .
  2. Check for poor connection at PCM 35-pin connector "A" terminals No. 20 and No. 32. Repair as necessary. If PCM connections are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  3. Check for open or short in Brown/Red wire, Gray/Red wire or Gray/Yellow wire between 3-pin fuel tank pressure sensor harness connector and PCM 35-pin connector "A". See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary. If wiring between fuel tank pressure sensor and PCM is okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC P0451: EVAPORATIVE (EVAP) CONTROL SYSTEM PRESSURE SENSOR PERFORMANCE

WARNINGThis work must be performed in a well ventilated area away from any open flame.

DTC is set when Power Control Module (PCM) detects fuel tank pressure is less than -5.3 kPa or more than 5.3 kPa for 5 seconds. MIL is illuminated when PCM detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. Fuel Tank Pressure (FTP) sensor or circuit malfunction.
  2. PCM malfunction.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Ensure DTCs P1450 and P1451 are not set. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle at speeds of 25 MPH for 1 second. Stop vehicle. Check for DTC P0451. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. If not using scan tool, go to next step. If using scan tool, turn ignition off. Connect scan tool to Data Link Connector (DLC). Remove fuel filler cap. Turn ignition on. Observe FUEL TANK PRESS reading on scan tool. If fuel tank pressure does not measure approximately zero kPa, go to step 3 . If fuel tank pressure measures approximately zero kPa, problem exists with fuel tank pressure control system. Test fuel tank pressure control system. See «FUEL EVAPORATION»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-system-component-testing) in SYSTEM & COMPONENT TESTING article. If fuel tank pressure control system checks okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  2. If diagnosing without scan tool, remove fuel filler cap. Remove PCM cover, located below right side of instrument panel. Connect DVOM (backprobe) between PCM 35-pin connector "A" terminals No. 20 (Brown/Red wire) and No. 32 (Gray/Yellow wire). Turn ignition on. If 2.0-2.5 volts does not exist, go to next step. If 2.0-2.5 volts exists, test fuel tank pressure control system. See «FUEL EVAPORATION»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-system-component-testing) in SYSTEM & COMPONENT TESTING article. If fuel tank pressure control system checks okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  3. Disconnect 12-pin fuel tank pressure sensor harness connector, located in left rear corner of vehicle. Connect DVOM between 12-pin fuel tank pressure sensor harness connector terminals No. 7 (Gray/Yellow wire) and No. 8 (Gray/Red wire). Turn ignition on. If 4.5-5.5 volts exists, go to next step. If 4.5-5.5 volts does not exist, go to step 6 .
  4. Check for open or short in Brown/Red wire between 12-pin fuel tank pressure sensor harness connector terminal No. 6 and PCM 35-pin connector "A" terminal No. 20. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary. If Brown/Red wire is okay, check for open in wiring between 12-pin fuel tank pressure sensor harness connector (located in left rear corner of vehicle) and 3-pin fuel tank pressure sensor harness connector, located at fuel tank. If wiring between 12-pin fuel tank pressure sensor harness connector and 3-pin fuel tank pressure sensor harness connector is okay, go to next step.
  5. Test fuel tank pressure control system. See «FUEL EVAPORATION»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-system-component-testing) in SYSTEM & COMPONENT TESTING article. If fuel tank pressure control system checks okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  6. Check for open or short in Gray/Red wire or Gray/Yellow wire between 12-pin fuel tank pressure sensor harness connector and PCM 35-pin connector "A". Repair as necessary. If Gray/Red wire and Gray/Yellow wire are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC P0461: FUEL LEVEL SENSOR CIRCUIT PERFORMANCE

Note. If DTC P0461 and P0463 are set together, diagnose DTC P0463 first.

DTC is set when change in fuel level signal is less than predetermined. MIL is illuminated when Power Control Module (PCM) detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. Fuel level sensor or circuit malfunction.
  2. Fuel level gauge malfunction.
  3. PCM malfunction.
  1. If not using scan tool, go to next step. If using scan tool, turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Observe FUEL TANK LEVEL reading on scan tool. Add approximately one gallon (3.8 liters) of fuel to tank. Observe FUEL TANK LEVEL reading on scan tool. If fuel level indicated on scan tool does not increase, go to step 3 . If fuel level indicated on scan tool increases, check for an intermittent problem. See «TROUBLE SHOOTING - NO CODES»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes) article. Repair as necessary and retest system. If all checks are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  2. If diagnosing without scan tool, remove PCM cover, located below right side of instrument panel. Connect DVOM (backprobe) between ground and PCM 35-pin connector "A" terminal No. 12 (Blue/White wire). Turn ignition on. Observe voltage reading. Add approximately one gallon (3.8 liters) of fuel to tank while observing voltage reading. If voltage increases, go to next step. If voltage decreases, check for an intermittent problem. See «TROUBLE SHOOTING - NO CODES»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes) article. Repair as necessary and retest system. If all checks are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  3. Turn ignition off. Disconnect 13-pin harness connector from instrument cluster. Disconnect PCM 35-pin connector "A". Connect DVOM to measure resistance between ground and PCM 35-pin connector "A" terminal No. 12 (Blue/White wire). Resistance should be 2-4 ohms with float level at full position. Resistance should be 119-121 ohms with float level at empty position. If actual fuel level is unknown, it may be necessary to remove fuel level sensor for inspection. If resistance is as specified, leave DVOM connected and go to next step. If resistance is not as specified, check for faulty fuel level sensor or wiring to fuel level sensor. See appropriate INSTRUMENT PANELS article in ELECTRICAL. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary and retest system.
  4. Connect 13-pin harness connector to instrument cluster. Connect PCM 35-pin connector "A". With DVOM still connected between ground and PCM 35-pin connector "A" terminal No. 12 (Blue/White wire), switch DVOM setting to measure voltage. Turn ignition on. Reading should be approximately .5 volt with float level at full position. Reading should be approximately 6 volts with float level at empty position. If voltage is as specified at both positions, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system. If voltage is not as specified at both positions, check for faulty wiring to instrument cluster. Repair as necessary. If wiring to instrument cluster checks okay, replace instrument cluster. See appropriate INSTRUMENT PANELS article in ELECTRICAL.

DTC is set when Power Control Module (PCM) detects fuel level sensor voltage is more than predetermined. MIL is illuminated when PCM detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. Fuel level sensor or circuit malfunction.
  2. Fuel level gauge malfunction.
  3. PCM malfunction.

Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article. Start engine and allow it to idle for 10 seconds. Check for DTC P0463. See RETRIEVING DTCS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.

  1. Turn ignition off. Disconnect 13-pin harness connector from instrument cluster. Remove PCM cover, located below right side of instrument panel. Connect DVOM (backprobe) between ground and PCM 35-pin connector "A" terminal No. 12 (Blue/White wire). Turn ignition on. If reading is approximately zero volt, go to next step. If reading is not approximately zero volt, repair short to power in Blue/White wire. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Retest system.
  2. Turn ignition off. Disconnect PCM 35-pin connector "A". Connect DVOM to measure resistance between ground and PCM 35-pin connector "A" terminal No. 12 (Blue/White wire). Resistance should be 2-4 ohms with float level at full position. Resistance should be 119-121 ohms with float level at empty position. If actual fuel level is unknown, it may be necessary to remove fuel level sensor for inspection. If resistance is as specified, go to next step. If resistance is not as specified, check for faulty fuel level sensor or wiring to fuel level sensor. See appropriate INSTRUMENT PANELS article in ELECTRICAL. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary and retest system.
  3. Connect 13-pin harness connector to instrument cluster. Connect DVOM (backprobe) between ground and PCM 35-pin connector "A" terminal No. 12 (Blue/White wire). Turn ignition on. Reading should be approximately .5 volt with float level at full position. Reading should be approximately 6 volts with float level at empty position. If voltage is not as specified at both positions, replace instrument cluster. See appropriate INSTRUMENT PANELS article in ELECTRICAL. If voltage is as specified at both positions, check for an intermittent problem. See «TROUBLE SHOOTING - NO CODES»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes) article. Repair as necessary and retest system. If all checks are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC is set when Power Control Module (PCM) detects no vehicle speed signal input with vehicle decelerating (fuel cut) for 4 seconds. Possible causes are

  1. VSS malfunction.
  2. VSS drive gear or driven gear malfunction.
  3. Speedometer malfunction.
  4. If equipped, cruise control module malfunction.
  5. PCM malfunction.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle with engine speed at 4000 RPM in 3rd gear (M/T) or 2nd gear (A/T). Release accelerator pedal and allow vehicle to coast (with vehicle in gear). Stop vehicle. Check for DTCs P0500. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. If speedometer does not indicate vehicle speed, go to next step. If speedometer indicates vehicle speed, check for any poor connections or faulty Blue/Yellow wire to speedometer. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary and retest system. If circuit is okay, problem is intermittent. See INTERMITTENTS in «TROUBLE SHOOTING - NO CODES»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes) article. If all checks are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  2. Ensure ignition is off. Disconnect VSS 3-pin harness connector. Turn ignition on. Using DVOM, measure voltage between VSS 3-pin harness connector terminals No. 2 (Black/Yellow wire) and No. 3 (Blue/Black wire). If 10-14 volts exists, go to next step. If 10-14 volts does not exist, check for faulty Black/Yellow wire or Blue/Black wire to VSS. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary and retest system.
  3. Using DVOM, measure voltage between VSS 3-pin harness connector terminals No. 1 (Blue/Yellow wire) and No. 2 (Black/Yellow wire). If 4 volts or more exists, go to next step. If less than 4 volts exists, leave DVOM connected and go to step 5 .
  4. Remove VSS. Check VSS drive and driven gears for damage or excessive wear. Repair or replace as needed. If no problems were found, check for poor connection to VSS. If connection is okay, replace VSS and retest system.
  5. Turn ignition off. Disconnect 16-pin harness connector from instrument cluster. Turn ignition on. With DVOM still connected between VSS 3-pin harness connector terminals No. 1 (Blue/Yellow wire) and No. 2 (Black/Yellow wire), observe voltage reading. If 4 volts or more exists, replace instrument cluster. See appropriate INSTRUMENT PANELS article in ELECTRICAL. Retest system. If less than 4 volts exists, leave DVOM connected and go to next step.
  6. Turn ignition off. Disconnect 12-pin cruise control module harness connector, located underhood on left fenderwell. Turn ignition on. With DVOM still connected between VSS 3-pin harness connector terminals No. 1 (Blue/Yellow wire) and No. 2 (Black/Yellow wire), observe voltage reading. If less than 4 volts exists, go to next step. If 4 volts or more exists, replace cruise control module. See appropriate CRUISE CONTROL article in ELECTRICAL. Retest system.
  7. Check Blue/Yellow wire for open or short between VSS, PCM, instrument cluster and cruise control module. Repair as necessary. If wiring and connections are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC P0505: IDLE AIR CONTROL (IAC) SYSTEM MALFUNCTION

Note. If DTC P0505 and P0500 are set together, diagnose DTC P0500 first. Also see ROUGH OR UNSTABLE IDLE under SYMPTOMS in TROUBLE SHOOTING - NO CODES article.

DTC is set when engine idle speed is 100 RPM lower than predetermined when IAC valve opening is about 100 percent. DTC also is set when engine idle speed is 200 RPM higher than predetermined when IAC valve opening is about zero percent. DTC is also set when IAC valve monitor voltage is high. MIL is illuminated when Power Control Module (PCM) detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. IAC valve malfunction.
  2. Air intake system plugged, leaking or fast idle control system malfunction.
  3. Vehicle Speed Sensor (VSS) malfunction.
  4. Mechanical engine malfunction.
  5. Excessive engine load.
  6. PCM malfunction.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Allow engine to idle for 30 seconds. Check for DTCs P0505. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. Ensure idle speed and IAC duty are within specifications. See «IDLE SPEED»(/suzuki/grand-vitara/i-1997-2001/remont/adjustments/#engine-controls-on-vehicle-adjustments__idle-speed) in ON-VEHICLE ADJUSTMENTS article. If idle speed and IAC duty are not within specifications, go to next step. If idle speed and IAC duty are within specifications, problem is intermittent. See INTERMITTENTS in «TROUBLE SHOOTING - NO CODES»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes) article. If all checks are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  2. Check idle air control valve operation. See «IDLE AIR CONTROL (IAC) VALVE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-system-component-testing) under IDLE CONTROL SYSTEM in SYSTEM & COMPONENT TESTING article. If idle air control valve operates as specified, go to step 5 . If operation is not as specified, go to next step.
  3. Turn ignition off. Remove PCM cover, located below right side of instrument panel. Disconnect PCM connectors. Connect one lead of ohmmeter to PCM 28-pin connector "D" terminal No. 14 (Violet/Black wire). Connect other lead of ohmmeter to PCM 28-pin connector "D" terminals No. 15 (Light Green/Black wire), No. 24 (Violet/Yellow wire) and No. 25 (Gray/Blue wire). Resistance on all circuits should be 40-48 ohms. If resistance readings are as specified, go to next step. If resistance readings are not as specified, Check for open or short circuits on appropriate wire(s). See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. If wiring and connectors are okay, replace IAC valve. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  4. Ensure ignition is off. Reconnect PCM connectors. Disconnect IAC valve harness connector. Turn ignition on. Using DVOM, measure voltage between ground and IAC valve harness connector terminals No. 2 and 5 (Blue/Black wires). If 10-14 volts exists on both wires, either IAC valve or PCM is defective. Replace as necessary. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. If 10-14 volts does not exist on both wires, repair open in Blue/Black wire between IAC valve and main relay. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary and retest system.
  5. Ensure intake system does not draw extra air (vacuum leaks, air cleaner connections, etc.). Repair as necessary. If intake system is okay, go to next step.
  6. Check engine mechanical condition. See appropriate article in ENGINES. If engine mechanical condition is okay, go to next step.
  7. Check for excessive external load on engine (power steering pump, air conditioning compressor, generator and transmission). Repair or replace as necessary. If no excessive external load on engine is found, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC is set when check sum is not equal to a predetermined value. Possible cause is an Power Control Module (PCM) malfunction.

Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article. Start engine and allow it to idle for 10 seconds. Check for DTC P0601. See RETRIEVING DTCS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.

Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Clear DTC(s). Start engine and run for one minute. If DTC P0601 resets, replace PCM. See REMOVAL, OVERHAUL & INSTALLATION article. Retest system. If DTC(s) did not reset, check for an intermittent problem. See TROUBLE SHOOTING - NO CODES article.

DTC is set when Power Control Module (PCM) detects MAP sensor output voltage, for predetermined amount of time with engine at operating temperature and running, and incorrect throttle opening voltage, of more than 2.7 volts or less than 1.1 volt. MIL is illuminated when PCM detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. MAP sensor or circuit malfunction.
  2. PCM malfunction.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Drive vehicle at speeds of 35 MPH with throttle steady for 30 seconds. Stop vehicle and allow engine to idle for 10 seconds. Check for DTC P1408. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. Remove PCM cover, located below right side of instrument panel. Connect DVOM (backprobe) between PCM 26-pin connector "B" terminals No. 13 (Red/White wire) and No. 20 (Gray/Yellow wire). Turn ignition on. Reading should be 4.0-5.0 volts. Start and idle engine. Reading should be 1.2-2.0 volts. If voltage readings are not as specified, go to next step. If voltage readings are as specified, check for intermittent problem. See INTERMITTENTS in «TROUBLE SHOOTING - NO CODES»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes) article. If all checks are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  2. Turn ignition off. Disconnect 3-pin Manifold Differential Pressure (MDP) sensor harness connector, located on top of engine near right side valve cover. Turn ignition on. Using DVOM, measure voltage between MDP sensor harness connector terminals No. 2 (Gray/Yellow wire) and No. 3 (Gray/Red wire). If 4.5-5.5 volts exists, go to next step. If 4.5-5.5 volts does not exist, go to step 4 .
  3. Check for open or short in Red/White wire between PCM and MDP sensor. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. If Red/White wire is okay, replace MDP sensor. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  4. Check for open or short in Gray/Red wire or Gray/Yellow wire between PCM and MDP sensor. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. If Gray/Red wire and Gray/Yellow wire are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC P1410 is set when there is a disagreement between Power Control Module (PCM) output signal to tank pressure control solenoid vacuum valve and monitor signal for 5 secons. MIL is illuminated when PCM detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. Tank pressure control solenoid vacuum valve or circuit malfunction.
  2. PCM malfunction.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article. Start engine. Drive vehicle at speeds of 25 MPH or more with throttle steady for one minute.
  2. Stop vehicle. Check for pending or set DTC P1410. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  1. Remove PCM cover, located below right side of instrument panel. Turn ignition on. Using DVOM, measure voltage (backprobe) between ground and PCM 26-pin connector "B" terminal No. 18 (Green/White wire). If 10-14 volts exists, leave DVOM connected and go to step 3 . If 10-14 volts does not exist, go to next step.
  2. Check for open or short in Blue/Black wire between fuel tank pressure control solenoid valve and main relay. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Check for open or short in Green/White wire between fuel tank pressure control solenoid valve and PCM. Repair as necessary and retest system. If Blue/Black wire and Green/White wire check okay, replace fuel tank pressure control solenoid valve. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  3. Start engine. With DVOM still connected between ground and PCM 26-pin connector "B" terminal No. 18 (Green/White wire), observe voltage reading. If 0-1 volt does not exist, go to next step. If 0-1 volt exists, check for intermittent problem. See INTERMITTENTS in «TROUBLE SHOOTING - NO CODES»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes) article. If all checks are okay, go to next step.
  4. Check for poor connection to PCM. If PCM connection is okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC P1450: BAROMETRIC PRESSURE SENSOR CIRCUIT MALFUNCTION OR DTC P1451: BAROMETRIC PRESSURE SENSOR PERFORMANCE PROBLEM

Note. Barometric pressure (BARO) sensor is an integral part of a PCM.

DTC P1450 is set when Power Control Module (PCM) detects that barometric pressure sensor is less than 0.1 volt or more than 5.1 volts. DTC P1451 is set when barometric pressure calculated using Manifold Absolute Pressure (MAP) sensor does not match barometric pressure sensor output voltage during engine deceleration. MIL is illuminated when PCM detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. Barometric pressure sensor (in PCM) malfunction.
  2. MAP sensor or circuit malfunction.
  1. Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See «MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__malfunction-indicator-light-mil-reset-procedure) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  2. Start engine and allow it to reach normal operating temperature. Allow engine to idle for 30 seconds. Check for DTCs P1450 and P1451. See «RETRIEVING DTCS»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-self-diagnostics-introduction__retrieving-dtcs) under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.

Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Clear DTC(s). Start engine. Increase engine speed to 2000 RPM momentarily. Return engine to idle and run for one minute. If DTC P1450 resets, replace PCM. See REMOVAL, OVERHAUL & INSTALLATION article. Retest system. If DTC P1451 resets, check Manifold Differential Pressure (MDP) sensor and vacuum passage referring to DTC P1408: MANIFOLD DIFFERENTIAL PRESSURE (MDP) SENSOR CIRCUIT MALFUNCTION . If sensor circuit and vacuum passage are okay, replace PCM. See REMOVAL, OVERHAUL & INSTALLATION article. Retest system. If codes do not reset, check for an intermittent problem. See TROUBLE SHOOTING - NO CODES article.

DTC is set when engine start signal is not detected by Power Control Module (PCM) when engine is started. DTC is also set when PCM detects engine start signal for 20 seconds or more while engine is running. MIL is illuminated when PCM detects malfunction during 2 consecutive drive cycles. Possible causes are

  1. Engine start signal circuit malfunction.
  2. PCM malfunction.

Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article. Start engine and allow it to idle for 5 minutes. Check for DTC P1500. See RETRIEVING DTCS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.

  1. Remove PCM cover, located below right side of instrument panel. Connect DVOM between ground and PCM 28-pin connector "D" terminal No. 26 (Black/Yellow wire). Start engine and observe voltage reading. If 0-1 volt exists, leave DVOM connected and go to next step. If 0-1 volt does not exist, repair short to power in Black/Yellow wire. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Retest system.
  2. Stop engine. With DVOM still connected between ground and PCM 28-pin connector "D" terminal No. 26 (Black/Yellow wire), crank engine and observe voltage reading. If 6-14 volts does not exist, check for open in Black/Yellow wire. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Repair as necessary and retest system. If Black/Yellow wire is okay, go to next step. If 6-14 volts exists, check for intermittent problem. See INTERMITTENTS in «TROUBLE SHOOTING - NO CODES»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes) article. If all checks are okay, go to next step.
  3. Replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.

DTC is set when Power Control Module (PCM) detects incorrect voltage at PCM back-up power supply. Battery voltage is supplied so that diagnostic trouble code memory values are not lost when ignition is turned off. Possible cause are

  1. Battery voltage supply circuit malfunction.
  2. PCM malfunction.

Ensure intake air temperature is 6.8-158°F (-14-70°C), vehicle is at an altitude of 9150 feet or below, and barometric pressure is 74 kPa or more. Turn ignition off, connect scan tool and turn ignition on. Clear DTCs. See MALFUNCTION INDICATOR LIGHT (MIL) RESET PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article. Start engine and allow it to idle for 10 seconds. Check for DTC P1510. See RETRIEVING DTCS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.

  1. Remove PCM cover, located below right side of instrument panel. Connect DVOM between ground and PCM 35-pin connector "A" terminal No. 35 (White wire). Start engine and observe voltage reading. If 10-14 volts does not exist, go to next step. If 10-14 volts exists, check for an intermittent problem. See «TROUBLE SHOOTING - NO CODES»(/suzuki/grand-vitara/i-1997-2001/remont/testing-diagnostics/#engine-controls-trouble-shooting-no-codes) article. If all checks are okay, replace PCM. See «REMOVAL, OVERHAUL & INSTALLATION»(/suzuki/grand-vitara/i-1997-2001/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) article. Retest system.
  2. Check for open DOME fuse No. 17 (15-amp) in instrument panel fuse block. Replace fuse and repair short as necessary. If fuse is okay, repair open in White wire between PCM and DOME fuse. See «WIRING DIAGRAMS»(/suzuki/grand-vitara/i-1997-2001/remont/wiring-diagrams-engine-performance/#engine-performance-wiring-diagrams) article. Retest system.

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