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Engine Controls - Self-Diagnostics: Diagnosis Mitsubishi Mirage V

Testing & Diagnostics 5 illustrations ~20170 words

DIAGNOSTIC TROUBLE CODE DEFINITIONS

Note. Listed DTCs are retrieved using a scan tool. See ENTERING ON-BOARD DIAGNOSTICS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.

Generic Scan Tool DTCDescription
No CodeECM Malfunction
P0100 (1)Volume Airflow Circuit Malfunction
P0105 (1)BARO Circuit Malfunction
P0105 (2)MAP Circuit Malfunction
P0110IAT Circuit Malfunction
P0110IAT Circuit Malfunction
P0115ECT Circuit Malfunction
P0120TPS Circuit Malfunction
P0125 (3)Excessive Time To Enter Closed Loop Fuel Control
P0130O2 Sensor Circuit Malfunction (Bank 1 Sensor 1)
P0135O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 1)
P0136O2 Sensor Circuit Malfunction (Bank 1 Sensor 2)
P0141O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 2)
P0150O2 Sensor Circuit Malfunction (Bank 2 Sensor 1)
P0155O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 1)
P0156O2 Sensor Circuit Malfunction (Bank 2 Sensor 2)
P0161O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 2)
P0170Fuel Trim Malfunction (Bank 1)
P0173Fuel Trim Malfunction (Bank 2)
P0201Injector No. 1 Circuit Malfunction
P0202Injector No. 2 Circuit Malfunction
P0203Injector No. 3 Circuit Malfunction
P0204Injector No. 4 Circuit Malfunction
P0205Injector No. 5 Circuit Malfunction
P0206Injector No. 6 Circuit Malfunction
P0300 (4)Random Misfire Detected
P0301 (4)Cylinder No. 1 Misfire Detected
P0302 (4)Cylinder No. 2 Misfire Detected
P0303 (4)Cylinder No. 3 Misfire Detected
P0304 (4)Cylinder No. 4 Misfire Detected
P0305 (4)Cylinder No. 5 Misfire Detected
P0306 (4)Cylinder No. 6 Misfire Detected
P0325 (5)Knock Sensor (KS) No. 1 Circuit
P0335CKP Sensor Circuit Malfunction
P0340CMP Sensor Circuit Malfunction
P0400EGR Flow Malfunction
P0403EGR Solenoid Malfunction
P0420Catalyst Efficiency Below Threshold (2.0L Turbo & Federal 2.4L)
P0421 (6)Warm Up Catalyst Efficiency Below Threshold (Bank 1 - California 2.4L)
P0431Warm Up Catalyst Efficiency Below Threshold (Bank 2 - California 2.4L)
P0442EVAP System Leak Detected
P0443EVAP Purge Control Valve Circuit Malfunction
P0446EVAP System Vent Control Malfunction
P0450EVAP System Pressure Sensor Malfunction Or Blocked System
P0455EVAP System Leak Or Blockage Detected
P0500Vehicle Speed Sensor (VSS) Malfunction
P0505Idle Control System Malfunction
P0510Closed Throttle Position Switch Malfunction
P0551Power Steering Pressure Sensor Circuit Range/Performance
P0705Transaxle Range Sensor Circuit Malfunction (A/T)
P0710Transaxle Fluid Temperature Sensor Circuit Malfunction (A/T)
P0715Input/Turbine Speed Sensor Malfunction (A/T)
P0720Output Speed Sensor Circuit Malfunction (A/T)
P0725Engine Speed Input Circuit Malfunction (A/T)
P0740Torque Converter Clutch System Malfunction (A/T)
P0750Shift Solenoid A Malfunction (A/T)
P0755Shift Solenoid B Malfunction (A/T)
P0760Shift Solenoid C Malfunction (A/T)
P0765Shift Solenoid D Malfunction (A/T)
P1101 (7)Vacuum Control Solenoid Valve System
P1102 (7)Ventilation Control Solenoid Valve System
P1400 (1)Manifold Differential Pressure Sensor Circuit Malfunction
P1500 (6)Generator FR Terminal Circuit Malfunction
P1600Serial Communication Link Malfunction (A/T)
P1751A/T Control Relay Malfunction (A/T)
P1795Throttle Position Input Circuit Malfunction (A/T)
(1) Except Mirage 1.5L. (2) Mirage 1.5L only. (3) MIL will illuminate on first detection of the malfunction (one-trip detection). For all other malfunctions, except severe misfire, MIL will illuminate when engine is next turned on and malfunction is again detected (two-trip detection). (4) If misfire is severe enough to cause catalytic converter damage, MIL will illuminate on first detection and continuously flash as long as danger is present (one-trip detection). If misfire is not severe enough to cause catalytic converter damage, but will cause emissions levels to increase 150 percent over Federal Test Procedure standards, a pending code will be set on first occurrence. If next time key is cycled on and off and misfire is detected under similar conditions to the first occurrence, MIL will illuminate (2-trip detection). (5) Diamante only. (6) Mirage only. (7) Diamante With Traction Control only.
(1)Except Mirage 1.5L.
(2)Mirage 1.5L only.
(3)MIL will illuminate on first detection of the malfunction (one-trip detection). For all other malfunctions, except severe misfire, MIL will illuminate when engine is next turned on and malfunction is again detected (two-trip detection).
(4)If misfire is severe enough to cause catalytic converter damage, MIL will illuminate on first detection and continuously flash as long as danger is present (one-trip detection). If misfire is not severe enough to cause catalytic converter damage, but will cause emissions levels to increase 150 percent over Federal Test Procedure standards, a pending code will be set on first occurrence. If next time key is cycled on and off and misfire is detected under similar conditions to the first occurrence, MIL will illuminate (2-trip detection).
(5)Diamante only.
(6)Mirage only.
(7)Diamante With Traction Control only.

DIAGNOSTIC TROUBLE CODE (DTC) INDEX

SCAN TOOL WILL NOT COMMUNICATE

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

DTC Set Criteria

  1. Engine speed is 500 RPM or more. Code will set if sensor output frequency is 3.3 Hz or less for 4 seconds.
  2. Throttle Position (TP) sensor voltage is 2 volts or less. Engine speed is 2000 RPM or less. Code will set if sensor output frequency is 800 Hz or more for 4 seconds.
  3. Throttle Position (TP) sensor voltage is more than 1.5 volts. Engine speed is more than 2000 RPM. Code will set if sensor output frequency is less than 60 Hz for 4 seconds.

Diagnostic Procedure

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Install Test Harness (MB991348 for Diamante, or MB991709 for Mirage) between VAF sensor harness connector and sensor. Start engine and allow it to idle. Check voltage between ground and VAF sensor connector terminal No. 3. If voltage is 2.2-3.2 volts, go to next step. If voltage is not as specified, go to step 3 .
  2. Check voltage between ground and VAF sensor connector terminal No. 7. Voltage should be 0-1 volt at idle and 6-9 volts at 3000 RPM. If voltage is as specified, replace ECM or TCM (if equipped). If voltage is not as specified, go to step 6 .
  3. Disconnect VAF sensor connector. Turn ignition on. Check voltage between ground and VAF sensor connector terminal No. 4. If battery voltage exists, go to next step. If battery voltage does not exist, check wiring harness between VAF sensor, fuel pump relay connector and MFI relay connector.
  4. Check voltage between ground and VAF sensor connector terminal No. 3. Voltage should be 4.8-5.2 volts. Check continuity between ground and VAF sensor connector terminal No. 5. If voltage is as specified and continuity exists, check VAF sensor connector. If connector is okay, replace VAF sensor. If voltage is not as specified or continuity does not exist, go to next step.
  5. Check VAF sensor connector and wiring harness between ECM and VAF sensor connector. If connector and wiring are okay, replace ECM.
  6. Turn ignition on. With ECM connector connected, check voltage between ground and ECM terminal No. 19. If voltage is 6-9 volts, check ECM connector. If connector is okay, replace ECM. If voltage is not as specified, check VAF sensor connector. If VAF sensor connector is okay, replace, VAF sensor.
  1. At least 2 seconds (Mirage) or 60 seconds (Diamante) have passed since engine started. Battery voltage is 8 volts or more. Code will set if sensor output voltage is 4.5 volts or more, or 1.95 volts or less, for 4 seconds.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Barometric pressure sensor is located in Volume Airflow (VAF) sensor. Install Test Harness (MB991348 for Diamante, or MB991709 for Mirage) between VAF sensor harness connector and VAF. Check voltage between ground and VAF sensor connector terminal No. 2. Voltage should be 3.7-4.3 volts at 0 ft. (0 m) to 3.2-3.8 volts at 3937 ft. (1200 m). If voltage is as specified, go to next step. If voltage is not as specified, go to step 3 .
  2. Turn ignition on. With ECM connector connected, check voltage between ground and ECM connector terminal No. 65 on Mirage, or ECM connector terminal No. 55 on Diamante. Voltage should be 3.7-4.3 volts at 0 ft. (0 m) to 3.2-3.8 volts at 3937 ft. (1200 m). If voltage is as specified, check ECM connector. If connector is okay, replace ECM. If voltage is not as specified, check wiring harness between ECM and VAF sensor.
  3. Disconnect VAF sensor connector. Turn ignition on. Check voltage between ground and VAF sensor connector terminal No. 1. Voltage should be 4.8-5.2 volts. Turn ignition off. Check continuity between ground and VAF sensor connector terminal No. 5. If voltage is as specified and continuity exists, go to next step. If voltage is not as specified or continuity does not exist, go to step 5 .
  4. Check VAF sensor connector and wiring harness between ECM and VAF sensor. If connector and wiring are okay, replace VAF sensor.
  5. Check ECM connector and wiring harness between ECM and VAF sensor connector. If connector and wiring are okay, replace ECM.
  1. Ignition switch is in ON position. Code will set when sensor output voltage is 4.5 volts or more for 2 seconds.
  2. Throttle Position (TP) sensor voltage is 1.25 volts or more. Engine speed is less than 4000 RPM. Code will set when TP sensor output voltage is .2 volt or less for 2 seconds.
  3. TP sensor voltage is .8 volt or less. Engine speed is less than 2000 RPM. Code will set when TP sensor output voltage is 4 volts or more for 2 seconds.
  4. TP sensor voltage is 3.5 volts or more. Engine speed is 2000 RPM or more. Code will set when TP sensor output voltage is 1.1 volts or less for 2 seconds.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Install Test Harness (MB991348) between MAP sensor harness connector and MAP sensor. Check voltage between ground and MAP sensor connector terminal No. 1. Voltage should be 0.9-1.5 volts at idle and should increase momentarily when accelerator pedal is suddenly depressed. If voltage is as specified, go to next step. If voltage is not as specified, go to step 3 .
  2. Turn ignition on. With ECM connector connected, check voltage between ground and ECM terminal No. 85. Voltage should be 0.9-1.5 volts with engine at idle. If voltage is not as specified, check wiring harness between ECM and VAF sensor. If voltage is as specified, check ECM connector for damage. If connector is okay, replace ECM.
  3. Disconnect MAP sensor connector. Turn ignition on. Check voltage between ground and MAP sensor connector terminal No. 3. Voltage should be 4.8-5.2 volts. Turn ignition off. Check continuity between ground and MAP sensor connector terminal No. 2. If voltage is as specified and continuity exists, go to next step. If voltage is not as specified or continuity does not exist, go to step 5 .
  4. Check MAP sensor connector and wiring harness between ECM and VAF sensor. If connector and wiring are okay, check MAP hose between MAP sensor and intake manifold plenum. If hose is okay, replace MAP sensor.
  5. Check ECM connector and wiring harness between ECM and VAF sensor connector. If connector and wiring are okay, replace ECM.
  1. At least 2 seconds (Mirage) or 60 seconds (Diamante) have passed since engine started. Code will set if sensor output voltage is 4.6 volts or more, or .2 volt or less, for 4 seconds.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Intake Air Temperature (IAT) sensor is located in Volume Airflow (VAF) sensor. Disconnect VAF sensor connector. Check resistance between VAF sensor terminals No. 5 and 6. Resistance should be 5.3-6.7 k/ohms at 32°F (0°C), 2.3-3.0 k/ohms at 68°F (20°C) or 0.30-0.42 k/ohms at 176°F (80°C). Check resistance while heating sensor with hair dryer. If resistance remains unchanged or increases as temperature is increased, replace VAF sensor. If resistance decreases, go to next step.
  2. Disconnect VAF sensor connector. Turn ignition on. Check voltage between ground and VAF sensor connector terminal No. 6. Voltage should be 4.5-4.9 volts. Check continuity between ground and VAF sensor connector terminal No. 5. If voltage is not as specified or continuity does not exist, go to next step. If voltage is as specified and continuity exists, check VAF sensor connector. If connector is okay, replace ECM.
  3. Check ECM connector and wiring harness between ECM and VAF sensor connector. If connector and wiring are okay, replace ECM.
  1. At least 2 seconds have passed since engine started. Code will set if sensor output voltage is 4.6 volts or more, or .2 volt or less, for 4 seconds.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Disconnect IAT sensor connector. Check resistance between IAT sensor terminals No. 1 and 2. Resistance should be 5.3-6.7 k/ohms at 32°F (0°C), 2.3-3.0 k/ohms at 68°F (20°C) or 0.30-0.42 k/ohms at 176°F (80°C). Check resistance while heating sensor with hair dryer. If resistance remains unchanged or increases as temperature is increased, replace IAT sensor. If resistance decreases, go to next step.
  2. Disconnect IAT sensor connector. Turn ignition on. Check voltage between ground and IAT sensor connector terminal No. 1. Voltage should be 4.5-4.9 volts. Check continuity between ground and IAT sensor connector terminal No. 2. If voltage is not as specified or continuity does not exist, go to next step. If voltage is as specified and continuity exists, check IAT sensor connector. If connector is okay, replace ECM.
  3. Check ECM connector and wiring harness between ECM and IAT sensor connector. If connector and wiring are okay, replace ECM.
  1. Code will set if ECT sensor output voltage is 4.6 volts or more, or .1 volt or less, for 2 seconds (Mirage) or 4 seconds (Diamante).
  2. ECT sensor output voltage increases from less than 1.6 volts to 1.6 volts or more. Code will set if ECT sensor output voltage is 1.6 volts or more for 5 minutes.
  3. Engine coolant temperature immediately after engine starts is less than 104°F (40°C). Code will set if engine coolant temperature does not increase to 104°F (40°C) 1-5 minutes after starting.
  4. Mirage - Engine coolant temperature was 68°F (20°C) on Federal models, or 44.6°F (7°C) on California vehicles, or more immediately before engine was shut off on last drive, and when engine was started on current drive. Code will set if engine coolant temperature fluctuates within 1.8°F (1°C) after 5 minutes have passed since engine was started. Time is not counted if intake air temperature is 140°F (60°C) or more, engine speed is 1500 RPM or less, volumetric efficiency is 25 percent or less or fuel is shut off during operation. ECM runs monitor only once during drive cycle.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Remove ECT sensor. Immerse ECT sensor probe in hot water and check resistance across sensor terminals, while heating ECT sensor. Resistance should be 5.1-6.5 k/ohms at 32°F (0°C), 2.1-2.7 k/ohms at 68°F (20°C), 0.9-1.3 k/ohms at 104°F (40°C) or 0.26-0.36 k/ohms at 176°F (80°C). If resistance is as specified, go to next step. If resistance is not as specified, replace ECT sensor.
  2. Turn ignition on. Check voltage between ground and ECT sensor connector terminal No. 1. Voltage should be 4.5-4.9 volts. Check continuity between ground and ECT sensor connector terminal No. 2. If voltage is not as specified or continuity does not exist, go to next step. If voltage is as specified and continuity exists, check ECT sensor connector. If ECT sensor connector is okay, replace ECM.
  3. Check ECM connector and wiring harness between ECM and ECT sensor connector. If connector and wiring are okay, replace ECM.
  1. Closed throttle position switch is in ON position. Code will set if sensor output voltage is 2 volts or more, or .2 volt or less, for 4 seconds.
  2. Diamante - Engine speed is more than 2000 RPM. Volumetric efficiency is less than 30 percent. Code will set if sensor output voltage is 4.6 volts or more for 4 seconds.
  3. Diamante - Engine speed is 500-4000 RPM. Volumetric efficiency is more than 60 percent. Code will set if sensor output voltage is less than .8 volt for 4 seconds.
  4. Mirage - Engine speed is 3000 RPM or less. Volumetric efficiency is 30 percent or less. Code will set if sensor output voltage is 4.6 volts or more for 2 seconds.
  5. Mirage - Engine speed is more than 2000 RPM. Volumetric efficiency is 60 percent or more. Code will set if sensor output voltage is .8 volt or less for 2 seconds.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Using scan tool, read data list item No. 26 (closed throttle position switch). Scan tool display should switch between ON (throttle at idle) and OFF (throttle open slightly). If display is as specified, go to step 6 . If display is not as specified, go to next step.
  2. Disconnect TP sensor connector. Check continuity between TP sensor terminals No. 1 and 2 on Diamante, or terminals No. 3 and 4 on Mirage. Continuity should exist with throttle at idle. Continuity should not exist when throttle is opened. If continuity is as specified, go to next step. If continuity is not as specified, adjust TP sensor. If adjustment does not repair problem, replace TP sensor.
  3. Disconnect TP sensor connector. Turn ignition on. Check voltage between ground and TP sensor connector terminal No. 2 on Diamante, or terminal No. 1 on Mirage. Voltage should be 4 volts or more on Diamante, or 4.8-5.2 volts on Mirage. Check continuity between ground and TP sensor connector terminal No. 1 on Diamante, or terminal No. 4 on Mirage. Continuity should exist. If voltage is as specified and continuity exists, go to next step. If voltage is not as specified or continuity does not exist, go to step 5 .
  4. Check TP sensor connector for damage. Repair or replace connector as necessary. If connector is okay, replace ECM.
  5. Check ECM connector and wiring harness between ECM and TP sensor connector. If connector and wiring are okay, replace ECM.
  6. Disconnect TP sensor connector. Check resistance between TP sensor connector terminals No. 1 and 4. Resistance should be 3.5-6.5 k/ohms. Check resistance between TP sensor connector terminals No. 3 and 4 on Diamante, or terminals No. 2 and 4 on Mirage. Slowly open and close throttle. Resistance should change smoothly in proportion to throttle opening. If resistance is not as specified, replace TP sensor. If resistance is as specified, go to next step.
  7. Turn ignition on. Check voltage between ground and TP sensor connector terminal No. 4 on Diamante, or terminal No. 1 on Mirage. Voltage should be 4.8-5.2 volts. Check continuity between ground and TP sensor connector terminal No. 1 on Diamante, or terminal No. 4 on Mirage. If voltage is as specified and continuity exists, go to next step. If voltage is not as specified or continuity does not exist, go to step 10 .
  8. Connect TP sensor connector. Turn ignition on. With ECM connector connected, check voltage between ground and ECM connector terminal No. 46 on Diamante, or ECM connector terminal No. 84 on Mirage. Voltage should be 0.3-1.0 volt with throttle at idle and 4.5-5.5 volts with throttle full open. Go to next step.
  9. If voltage is not as specified, check TP sensor connector and wiring harness between ECM and TP sensor connector. If voltage is as specified, check ECM connector. If connector is okay, replace ECM.
  10. Check ECM connector and wiring harness between ECM and TP sensor connector. If connector and wiring are okay, replace ECM.
  1. Engine coolant temperature is more than 176°F (80°C). Intake air temperature is more than 14°F (-10°C). Atmospheric pressure is more than 11 psi (76 kPa). Engine speed is 1800-3500 RPM (Diamante) or 1800-4000 RPM (Mirage). Volumetric efficiency is 16-62 percent. Engine is in closed loop operation. Monitor runs once per trip for 128 seconds. Code will set if fuel injection system does not enter closed loop within 30 seconds of meeting listed parameters.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Disconnect front Heated Oxygen Sensor (HO2S) connector. On California Diamante, test applies to both front HO2S. Connect Test Harness (MD991223 on Diamante, or MD998464 on Mirage) to front HO2S. Using DVOM, check resistance (at room temperature) between test harness terminals No. 3 and 4 on Diamante Federal, terminals No. 1 and 3 on Diamante California or Mirage. Resistance should be 1-40 ohms on Federal Diamante, or 4.5-8 ohms on California Diamante or California Mirage. Resistance on Federal Mirage is 11-18 ohms. If resistance is as specified, go to next step. If resistance is not as specified, replace front HO2S.
  2. Start and warm engine until engine coolant temperature is 176°F (80°C) or more. Connect jumper wire between battery positive and test harness terminal No. 3 on Federal Diamante, terminal No. 1 on California Diamante, or terminal No. 1 on Mirage. Connect second jumper wire between battery negative terminal and test harness terminal No. 4 on Federal Diamante, terminal No. 3 on California Diamante, or terminal No. 3 on Mirage. Connect DVOM between test harness terminals No. 1 and 2 on Federal Diamante, or terminals No. 2 and 4 on California Diamante or Mirage. Check front HO2S output voltage, while repeatedly racing engine. If voltage is 0.6-1.0 volt, go to next step. If voltage is not as specified, replace front HO2S.
  3. Check connectors and wiring harness between front HO2S and ECM. Repair connectors or wiring as necessary. If wiring and connectors are okay, Go to next step.
  4. Disconnect fuel injector connector. Check resistance across fuel injector terminals. Resistance at 68°F (20°C) should be 13-16 ohms. If resistance is as specified, go to next step. If resistance is not as specified, replace fuel injector.
  5. Using stethoscope, check injector operating sound during cranking or at idle. Ensure frequency of operating sound increases as engine RPM increases. If injectors are okay, go to next step. If no operating sound is heard from an injector, check injector drive circuit. If drive circuit is okay, injector or ECM is suspect.
  6. Check fuel injector connectors, ECM connector and wiring harness between ECM and injector connectors. If wiring and connectors are okay, perform fuel pressure test. See FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURES article. If fuel pressure is okay, go to next step.
  7. Check for air being drawn into air intake or exhaust system. Check for exhaust leaks at HO2S fittings, exhaust manifold or front pipes. Check for fuel filter and/or fuel line blockage. Check fuel pump for poor fuel supply. If no problems are found, replace ECM.
  1. HO2S signal voltage is .1 volt or less (Diamante) or .2 volt or less (Mirage) for 3 minutes or more after engine started. Engine coolant temperature is more than 176°F (80°C). Engine speed is more than 1200 RPM. Volumetric efficiency is 25 percent or more. Intake air temperature is more than 14°F (-10°C). Atmospheric pressure is more than 11 psi (76 kPa). Code will set if input voltage supplied to ECM interface circuit is 4.5 volts or more when 5 volts are applied to HO2S output line via a resistor.
  2. Engine coolant temperature is 122°F (50°C) or more. Engine speed is 1250-3000 RPM (Diamante), 1600-3000 RPM (Mirage M/T) or 1400-3000 RPM (Mirage M/T). Volumetric efficiency is 25-60 percent. Intake air temperature is more than 14°F (-10°C). Atmospheric pressure is more than 11 psi (76 kPa). Engine is in closed loop control. Throttle valve angle not changing. Monitor runs once per trip for 5-20 seconds. Code will set if, when computer forcibly changes air-fuel ratio, HO2S signal does not respond to lean/rich change within 1.2 second.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Disconnect appropriate front Heated Oxygen Sensor (HO2S) connector. Connect Test Harness (MD991223 on Diamante, or MD998464 on Mirage) to front HO2S. Using DVOM, check resistance (at room temperature) between test harness terminals No. 3 and 4 on Diamante Federal, terminals No. 1 and 3 Diamante California or Mirage. Resistance should be 1-40 ohms on Federal Diamante, and 4.5-8 ohms on California Diamante or California Mirage. On Federal Mirage, resistance should be 11-18 ohms. If resistance is as specified, go to next step. If resistance is not as specified, replace front HO2S.
  2. Start and warm engine until engine coolant temperature is 176°F (80°C) or more. Connect jumper wire between battery positive terminal and test harness terminal No. 3 on Federal Diamante, or terminal No. 1 on California Diamante or Mirage. Connect second jumper wire between battery negative terminal and test harness terminal No. 4 on Federal Diamante, or terminal No. 3 on California Diamante or Mirage. Connect DVOM between test harness terminals No. 1 and 2 on Federal Diamante, or terminals No. 2 and 4 on California Diamante or Mirage. Check front HO2S output voltage, while repeatedly racing engine. If voltage is 0.6-1.0 volt, go to next step. If voltage is not as specified, replace front HO2S.
  3. Check connectors and wiring harness between front HO2S and ECM. Repair connectors or wiring as necessary. If wiring and connectors are okay, replace front HO2S. Clear DTCs and go to next step.
  4. Test drive vehicle following OBD-II drive cycle pattern. See HEATED OXYGEN SENSOR MONITOR and OTHER MONITOR under OBD-II DRIVE CYCLES in SELF-DIAGNOSTICS - INTRODUCTION article. Check readiness test status for HO2S monitor. If readiness test status is complete, check DTCs. If readiness test status is incomplete, run HO2S drive cycle again. Then check for DTCs. IF DTC P0130 or P0150 resets, replace ECM.
  1. Battery voltage is 11-16 volts. Monitor runs once per trip. Code will set if heater current of front HO2S heater is more than 3.5 amps, or less than .2 amp, for 6 seconds.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Disconnect appropriate front Heated Oxygen Sensor (HO2S) connector. Connect Test Harness (MD991223 on Diamante, or MD998464 on Mirage) to front HO2S. Using DVOM, check resistance (at room temperature) between test harness terminals No. 3 and 4 on Diamante Federal, or terminals No. 1 and 3 on Diamante California or Mirage. Resistance should be 1-40 ohms on Federal Diamante, or 4.5-8 ohms on California Diamante or California Mirage. Resistance on Federal Mirage should be 11-18 ohms. If resistance is as specified, go to next step. If resistance is not as specified, replace front HO2S.
  2. Start and warm engine until engine coolant temperature is 176°F (80°C) or more. Connect jumper wire between battery positive terminal and test harness terminal No. 3 on Federal Diamante, or terminal No. 1 on California Diamante or Mirage. Connect second jumper wire between battery negative terminal and test harness terminal No. 4 on Federal Diamante, or terminal No. 3 on California Diamante or Mirage. Connect DVOM between test harness terminals No. 1 and 2 on Federal Diamante, or terminals No. 2 and 4 on California Diamante or Mirage. Check front HO2S output voltage, while repeatedly racing engine. If voltage is 0.6-1.0 volt, go to next step. If voltage is not as specified, replace front HO2S.
  3. Check connectors and wiring harness between front HO2S and ECM. Repair connectors or wiring as necessary. If wiring and connectors are okay, Go to next step.
  4. Disconnect test harness. Turn ignition on. Check voltage between ground and front HO2S connector terminal No. 3 on Diamante or terminal No. 1 on Mirage. If battery voltage exists, go to next step. If battery voltage does not exist, check ECM connector and wiring harness between front HO2S connector and MFI relay.
  5. Disconnect ECM connectors B-108 and B-109 on Diamante, or ECM connector B-38 on Mirage. Turn ignition on. On Diamante, ground ECM connector B-109 terminal No. 49. Then check voltage between ground and ECM connector B-108 terminal No. 3. On Mirage, check voltage between ground and ECM connector B-38 terminal No. 60. If battery voltage does not exist, check connectors and wiring harness between front HO2S connector and ECM. If battery voltage exists, check ECM connector. If connector is okay, replace ECM.
  1. HO2S signal voltage is .1 volt or less for 3 minutes or more after engine is started. Engine coolant temperature is 176°F (80°C) or more. Engine speed is more than 1200 RPM. Volumetric efficiency is 25 percent or more. Intake air temperature is more than 14°F (-10°C). Atmospheric pressure is more than 11 psi (76 kPa). Monitor runs 7-10 seconds. Code will set if input voltage to ECM interface circuit is 4.5 volts or more when 5 volts is applied to HO2S output line via a resistor.
  2. Same conditions as previous listed criteria must be met. Code will set if HO2S output does not increase .1 volt or more in response to ECM making air-fuel ratio 15 percent richer.
  3. Mirage - Engine coolant temperature is 176°F (80°C) or more. Front HO2S is operating. Engine runs at least 10 seconds with rich air-fuel ratio. Rear HO2S output voltage is .4 volt or more before fuel shut-off starts. Monitor runs while fuel is shut off. Code will set if at least one second passes before rear HO2S output voltage falls to .15-.40 volt, or at least 3 seconds have passed before rear HO2S output voltage falls to .15 volt or less.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Disconnect appropriate rear HO2S connector. On Mirage with California emissions, install Test Harness (MD998464) between HO2S and HO2S connector. On all models, use a DVOM to check resistance between rear HO2S terminals No. 3 and 4 on Federal Diamante and Mirage, or terminals No. 1 and 3 on California Diamante. Resistance at 68°F (20°C) should be 7-40 ohms on Diamante. Resistance on Mirage should be 11-18 ohms. If resistance is as specified, go to next step. If resistance is not as specified, replace rear HO2S.
  2. Check rear HO2S connector, ECM connector and wiring harness between rear HO2S connector and ECM. If wiring and connectors are okay, replace rear HO2S. Clear DTCs and go to next step.
  3. Test drive vehicle following OBD-II drive cycle pattern. See HEATED OXYGEN SENSOR MONITOR and OTHER MONITOR under OBD-II DRIVE CYCLES in SELF-DIAGNOSTICS - INTRODUCTION article. Check readiness test status for heated oxygen sensor monitor. If readiness test status is complete, repair is verified. If readiness test status is incomplete, drive vehicle in OBD-II heated oxygen sensor monitor pattern again. Check scan tool for DTCs. If DTC P0136 or P0156 resets, replace ECM.
  1. Battery voltage is 11-16 volts. Monitor runs once per trip. Code will set if heater current of rear HO2S is more than 3.5 amps, or less than .2 amp, for 6 seconds.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Disconnect appropriate rear HO2S connector. On Mirage with California emissions, install Test Harness (MD998464) between HO2S and HO2S connector. On all models, use a DVOM to check resistance between rear HO2S terminals No. 3 and 4 on Federal Diamante and Mirage, or terminals No. 1 and 3 on California Diamante. Resistance at 68°F (20°C) should be 7-40 ohms on Diamante. Resistance on Mirage should be 11-18 ohms. If resistance is as specified, go to next step. If resistance is not as specified, replace rear HO2S.
  2. Disconnect rear HO2S connector. Using DVOM, check voltage between ground and HO2S connector terminal No. 1 on Diamante and Mirage with California emissions, or terminal No. 3 on Diamante and Mirage with Federal emissions. If battery voltage does not exist, check connectors and wiring harness between rear HO2S and MFI relay. If battery voltage exists, go to next step.
  3. Disconnect ECM connectors B-108 and connector B-109 on Diamante, or ECM connector B-38 on Mirage. Turn ignition on. On Diamante, ground ECM connector B-109 terminal No. 49. Then check voltage between ground and ECM connector B-108 terminal No. 26 (Federal) or No. 27 (California). On Mirage, check voltage between ground and ECM connector B-38 terminal No. 54. If battery voltage does not exist, check connectors and wiring harness between rear HO2S connector and ECM. If battery voltage exists, check ECM connector. If connector is okay, replace ECM.
  1. Engine is in closed loop control. Intake air temperature is more than 14°F (-10°C). Atmospheric pressure is more than 11 psi (76 kPa). Code will set if long-range fuel correction is +12.5 percent or more, or short-range fuel correction is -10-11.9 percent on Diamante, or -10-10 percent on Mirage, for 10 seconds (Diamante) or 5 seconds (Mirage).

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Using scan tool, read data list item No. 13 (intake air temperature). If temperature displayed on scan tool is equal to actual air temperature, go to next step. If temperature displayed on scan tool is not equal to actual air temperature, check air temperature circuit. See «DTC P0110: INTAKE AIR TEMPERATURE (IAT) CIRCUIT MALFUNCTION»(ref-91121-S19396903782001030200000) .
  2. Using scan tool, read data list item No. 21 (engine coolant temperature). If temperature displayed on scan tool is equal to actual engine coolant temperature, go to next step. If temperature displayed on scan tool is not equal to actual coolant temperature, check engine coolant temperature circuit. See «DTC P0115: ENGINE COOLANT TEMPERATURE (ECT) CIRCUIT MALFUNCTION»(ref-91121-S11615245452001030200000) .
  3. Turn ignition on (engine off). Using scan tool, read data list item No. 25 (barometric pressure) on Diamante and Mirage 1.8L. On Mirage 1.5L, read data list item No. 32 (manifold absolute pressure). Reading should be 101 kPa at 0 ft. (0 m), 95 kPa at 1969 ft. (600 m), 88 kPa at 3937 ft. (1200 m) or 81 kPa at 5906 ft. (1800 m). If scan tool reading is as specified, go to next step. If scan tool reading is not as specified on Diamante and Mirage 1.8L, check barometric pressure circuit. See «DTC P0105: BAROMETRIC PRESSURE CIRCUIT MALFUNCTION»(ref-91121-S31092339262001030200000) . On Mirage 1.5L, check MAP sensor circuit. See «DTC P0105: MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR CIRCUIT MALFUNCTION»(ref-91121-S31092339262001030200000) .
  4. Disconnect fuel injector connector. Check resistance across fuel injector terminals. Resistance at 68°F (20°C) should be 13-16 ohms. If resistance is as specified, go to next step. If resistance is not as specified, replace fuel injector.
  5. Using stethoscope, check injector operating sound during cranking or at idle. Ensure frequency of operating sound increases as engine RPM increases. If injectors are okay, go to next step. If no operating sound is heard from an injector, check injector drive circuit. If drive circuit is okay, injector or ECM is suspect.
  6. Check fuel injector connectors, ECM connector and wiring harness between ECM and injector connectors. If wiring and connectors are okay, perform fuel pressure test. See FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURES article. If fuel pressure is okay, go to next step.
  7. Using scan tool, read data list item No. 81 (long-term fuel compensation). If fuel trim is less than zero (during closed loop), go to next step. If fuel trim is more than zero (during closed loop), go to step 9 .
  8. On Mirage 1.5L, go to step 11 . Using scan tool, read data list item No. 12 (volume airflow). Reading should be from 18-44 Hz at idle. At 2500 RPM, reading should be 43-83 Hz on Diamante or 68-108 Hz on Mirage. Check that frequency (VAF volume) increases as RPM is increased. If scan tool reading is more than specification, replace VAF sensor. If scan tool reading is less than or equal to specification, check injectors for leakage and fuel for contamination. If injectors and fuel are okay, replace ECM.
  9. Check air intake system for leaks or obstructions. If air intake system is okay, use scan tool to read data list item No. 12 (volume airflow). Reading at idle should be 18-44 Hz. At 2500 RPM reading should be 68-108 Hz on Mirage, or 43-83 Hz on Diamante. Ensure frequency (VAF volume) increases as RPM is increased. If scan tool reading is less than specification, replace VAF sensor. If scan tool reading is more than or equal to specification, go to next step.
  10. Check injectors for blockage. Check fuel filter and fuel line for blockage. Check fuel pump for insufficient fuel volume. Check for exhaust leaks at HO2S fittings, exhaust manifold, or front pipes. Check for fuel contamination. If no problems are found, replace ECM.
  11. Check injectors for leakage and fuel for contamination. If injectors and fuel are okay, replace ECM.
  1. Engine speed is 50-1000 RPM. Throttle Position (TP) sensor output voltage is 1.16 volts or less. Code will set if injector surge voltage (system voltage plus 2 volts) is not detected for 4 seconds (Diamante) or 2 seconds (Mirage).

Note. DTCs P0205 and P0206 for injectors No. 5 and 6 apply to Diamante only. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Disconnect fuel injector connector. Check resistance across fuel injector terminals. If resistance at 68°F (20°C) is 13-16 ohms, go to next step. If resistance is not as specified, replace fuel injector.
  2. Using stethoscope, check injector operating sound during cranking or at idle. Ensure frequency of operating sound increases as engine RPM increases. If injectors are okay, go to next step. If no operating sound is heard from an injector, check injector drive circuit. If drive circuit is okay, injector or ECM is suspect.
  3. Check fuel injector connectors, ECM connector and wiring harness between ECM and injector connectors. If wiring and connectors are okay, go to next step.
  4. Disconnect fuel injector connectors. Turn ignition on. Check voltage between ground and each injector connector terminal No. 1. If battery voltage exists at all connectors, go to next step. If battery voltage does not exist at any one or all connectors, check connectors and wiring harness between ECM and fuel injector connectors.
  5. Connect fuel injector connectors. On Diamante, disconnect ECM connector B-108. On Mirage, disconnect ECM connector B-40. Turn ignition on. On Diamante, check voltage between ground and ECM connector B-108 terminals No. 1, 2, 9, 10, 24 and 25. On Mirage, check voltage between ground and ECM connector B-40 terminals No. 1, 2, 14 and 15. On all models, if battery voltage exists at all terminals, check ECM connector. If connector is okay, replace ECM. If battery voltage does not exist at any one or all terminals, check fuel injector connectors and wiring harness between ECM and injector connector.
  1. Engine speed is 500-6000 RPM. Engine coolant temperature is more than 14°F (-10°C). Intake air temperature is more than 14°F (-10°C). Atmospheric pressure is more than 11 psi (76 kPa). Adaptive learning is complete for vane which generates crankshaft position signal. No sudden accelerations or decelerations are occurring. Misfire is determined by change in angular velocity of Crankshaft Position (CKP) sensor. Code will set if misfire occurred in 4 or more of last 200 revolutions (severe misfire which will cause MIL to flash continuously). Also, code will set if misfire occurred in 20 or more of last 1000 revolutions.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Connect an external tachometer. Using scan tool, read data list item No. 22 (crankshaft position sensor). Check engine RPM during cranking and at idle. If RPM displayed on scan tool and tachometer are equal, go to next step. If RPM displayed on scan tool and tachometer are not equal, go to step 4.
  2. Using oscilloscope, perform crankshaft position sensor wave form check. Connect Test Harness (MD991348) between Crankshaft Position (CKP) sensor and harness connector. Connect analyzer special patterns pick-up to CKP sensor terminal No. 2. If test harness is not available, connect analyzer special patterns pick-up to ECM connector B-109 terminal No. 45 on Diamante, or ECM connector B-37 terminal No. 89 on Mirage. Go to next step.
  3. With engine idle speed stable, compare CKP sensor wave pattern to known-good wave pattern. (Scheme 86) If wave pattern is okay, go to step 5. If wave pattern is not okay, go to next step.
  4. Check CKP sensor connector, ECM connector and wiring harness between ECM and CKP sensor connector. Check CKP sensor and sensing plate for proper installation. If wiring, connectors and sensor installation are okay, replace CKP sensor.
  5. Disconnect fuel injector connector. Check resistance across fuel injector terminals. If resistance at 68°F (20°C) is 13-16 ohms, go to next step. If resistance is not as specified, replace fuel injector.
  6. Using stethoscope, check injector operating sound during cranking or at idle. Ensure frequency of operating sound increases as engine RPM increases. If injectors are okay, go to next step. If no operating sound is heard from an injector, check injector drive circuit. If drive circuit is okay, injector or ECM is suspect.
  7. Start and warm engine. Turn all accessories off. Increase engine speed to 2500 RPM. Using scan tool, read data list item No. 81 (long-term fuel compensation). If fuel trim is -12.5-12.5 percent (during closed loop), go to next step. If fuel trim is not as specified, check fuel trim fault. See «DTC P0170: FUEL TRIM MALFUNCTION»(ref-91121-S31429543792001030200000).
  8. Using scan tool, read data list item No. 82 (short-term fuel compensation). If fuel trim is -20.0-20.0 percent on Diamante, or -17-17 percent on Mirage (during closed loop), go to next step. If fuel trim is not as specified, check fuel trim fault. See «DTC P0170: FUEL TRIM MALFUNCTION»(ref-91121-S31429543792001030200000).
  9. Using scan tool, read data list item No. 21 (engine coolant temperature). If temperature displayed on scan tool is equal to actual engine coolant temperature, go to next step. If temperature displayed on scan tool is not equal to actual engine coolant temperature, check ECT circuit. See «DTC P0115: ENGINE COOLANT TEMPERATURE (ECT) CIRCUIT MALFUNCTION»(ref-91121-S11615245452001030200000).
  10. Check ignition coil, spark plugs and spark plug wires. On Mirage, check EGR system, EGR valve and for jumped timing belt. On all models, check compression pressure. See BASIC DIAGNOSTIC PROCEDURES article.

Scheme 86

Scheme 86
Scheme 86
  1. Engine speed is 500-6000 RPM. Engine coolant temperature is more than 14°F (-10°C). Intake air temperature is more than 14°F (-10°C). Atmospheric pressure is more than 11 psi (76 kPa). Adaptive learning is complete for vane which generates crankshaft position signal. No sudden accelerations or decelerations are occurring. Misfire is determined by change in angular velocity of Crankshaft Position (CKP) sensor. Code will set if misfire occurred 4 or more times during last 200 revolutions (severe misfire which will cause MIL to flash continuously). Also, code will set if misfire occurred in 20 or more of last 1000 revolutions.

Note. DTCs P0305 and P0306 for cylinders No. 5 and 6 apply to Diamante only. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Disconnect fuel injector connector. Check resistance across fuel injector terminals. If resistance at 68°F (20°C) is 13-16 ohms, go to next step. If resistance is not as specified, replace fuel injector.
  2. Using stethoscope, check injector operating sound during cranking or at idle. Ensure frequency of operating sound increases as engine RPM increases. If operating sound is okay, go to next step. If no operating sound is heard from an injector, check injector drive circuit. If drive circuit is okay, injector or ECM is suspect.
  3. Check connectors and wiring harness between ECM and injector. If wiring harness is okay, go to next step.
  4. Check spark plugs and spark plug wires. Check compression pressure. See BASIC DIAGNOSTIC PROCEDURES article.
  1. Ignition switch is in ON position. At least 60 seconds have passed since ignition switch was turned on or engine started. Engine speed is more than 3000 RPM. Code will set if knock sensor voltage has not changed more than .06 volt in last consecutive 200 periods (3 periods per crankshaft revolution).

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Disconnect KS connector. Check continuity between ground and KS connector terminal No. 2. If continuity exists, go to next step. If continuity does not exist, check wiring harness between ground and KS connector.
  2. Check KS connector, ECM connector B-110 and wiring harness between ECM and KS connector. If wiring and connectors are okay, replace KS. Clear DTCs and go to next step.
  3. Test drive vehicle following OBD-II drive cycle pattern. See OTHER MONITOR under OBD-II DRIVE CYCLES in SELF-DIAGNOSTICS - INTRODUCTION article. Check scan tool for DTCs. If DTC P0325 resets, replace ECM.
  1. Engine is being cranked. Code will set if CKP sensor voltage has not changed for 4 seconds.
  2. Engine is running. Code will set if normal signal pattern has not been input for cylinder identification from CKP sensor and Camshaft Position (CMP) sensor for 4 seconds (Diamante) or 2 seconds (Mirage).

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Connect Test Harness (MD998478) between CKP sensor and harness connector. Check voltage between ground and test harness terminal No. 2. Voltage should be 0.4-4.0 volts, while cranking engine and 1.5-2.5 volts with engine idling. If voltage is not as specified, go to next step. If voltage is as specified, replace ECM.
  2. Disconnect CKP sensor connector. Turn ignition on. Check voltage between ground and CKP sensor connector terminal No. 3. If battery voltage exists, go to next step. If battery voltage does not exist, check wiring harness between MFI relay connector and CKP sensor.
  3. Check voltage between ground and CKP sensor connector terminal No. 2. Voltage should be 4.8-5.2 volts. If voltage is as specified, go to next step. If voltage is not as specified, check ECM connector and wiring harness between CKP sensor connector and ECM. If connector and wiring are okay, replace ECM.
  4. Check continuity between ground and CKP sensor connector terminal No. 1. If continuity exists, check CKP sensor connector. If connector is okay, replace CKP sensor. If continuity does not exist, check wiring harness between ground and CKP sensor.
  1. Engine is being cranked. Code will set if CKP sensor voltage has not changed for 4 seconds (Diamante) or 2 seconds (Mirage).
  2. Engine is running. Code will set if normal signal pattern has not been input for cylinder identification from CKP sensor and Camshaft Position (CMP) sensor for 4 seconds (Diamante) or 2 seconds (Mirage).

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. With CMP sensor connector connected. Check voltage between ground and CMP sensor connector terminal No. 5 on Diamante and Mirage 1.5L, or terminal No. 2 on Mirage 1.8L. Voltage should be 0.4-3.0 volts, while cranking engine and 0.5-2.0 volts with engine idling. If voltage is as specified, go to next step. If voltage is not as specified, replace ECM.
  2. Disconnect CMP sensor connector. Turn ignition on. Check voltage between ground and CMP sensor connector terminal No. 6 on Diamante and Mirage 1.5L, or terminal No. 3 on Mirage 1.8L. If battery voltage exists, go to next step. If battery voltage does not exist, check wiring harness between MFI relay connector and CMP sensor.
  3. Check voltage between ground and CMP sensor connector terminal No. 5 on Diamante and Mirage 1.5L, or terminal No. 2 on Mirage 1.8L. If voltage is 4.8-5.2 volts, go to next step. If battery voltage is not 4.8-5.2 volts, check ECM connector and wiring harness between CMP sensor connector and ECM. If connector and wiring are okay, replace ECM.
  4. Check continuity between ground and CMP sensor connector terminal No. 7 on Diamante and Mirage 1.5L, or terminal No. 1 on Mirage 1.8L. If continuity exists, check CMP sensor connector. If connector is okay, replace distributor (Diamante and Mirage 1.5L) or CMP sensor (Mirage 1.8L). If continuity does not exist, check wiring harness between ground and CMP sensor.
  1. Engine coolant temperature is more than 176°F (80°C). Engine speed is 1000-2000 RPM. Intake air temperature is more than 41°F (5°C). Atmospheric pressure is more than 11 psi (76 kPa). Closed throttle position switch is on. Volumetric efficiency is less than 25 percent. Monitor runs for 2 seconds once per trip (Diamante) or 3 times per trip (Mirage). Code will set if, when EGR solenoid is turned on, intake air system barely changes.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. On Diamante, remove engine cover. On all models, install a "T" fitting between Green-striped vacuum hose and EGR valve. Connect hand vacuum pump to "T" fitting. Start engine. Monitor vacuum while racing engine. If engine coolant temperature is 68°F (20°C) or less, vacuum should not exist. If engine coolant temperature is 176°F (80°C) or more, vacuum should momentarily increase to more than 3.9 in. Hg. If vacuum is as specified, go to step 5 . If vacuum is not as specified, go to next step.
  2. Disconnect "T" fitting. Connect hand vacuum pump directly to EGR valve. Start engine. Apply 8.7 in. Hg. If engine stalls or idle becomes unstable, go to next step. If engine does not stall and idle does not become unstable, replace EGR valve.
  3. Turn engine off. Label and disconnect vacuum hoses from solenoid valve. Disconnect electrical connector. Connect hand vacuum pump to solenoid valve fitting where Green-striped hose (Diamante) or White-striped hose (Mirage) was connected. Apply vacuum to solenoid valve. Vacuum should leak.
  4. Apply battery voltage across terminals of solenoid valve. Vacuum should hold when voltage is applied to terminals. Using an ohmmeter, check resistance across solenoid valve terminals. If resistance at 68°F (20°C) is 36-44 ohms, go to next step. If resistance is not as specified, replace solenoid valve.
  5. On Mirage 1.5L, go to step 7 . On all other models, using scan tool, read data list item No. 95 (manifold differential pressure). Scan tool reading should be 22.6-36.0 kPa on Diamante, or 28.0-42.0 kPa on Mirage. Go to next step.
  6. If scan tool reading is as specified, check EGR valve and EGR passage for blockage. If scan tool reading is not as specified, check Manifold Differential Pressure (MDP) circuit. See «DTC P1400: MANIFOLD DIFFERENTIAL PRESSURE (MDP) SENSOR CIRCUIT MALFUNCTION»(ref-91121-S16628883852001030200000) .
  7. Ensure engine coolant is at 176-203°F (80-95°C). Turn all accessories off. Place gear selector in Park (A/T) or Neutral (M/T). Turn ignition on. Go to next step.
  8. Using scan tool, read data list item No. 32 (manifold absolute pressure). Scan tool reading should be as specified. See «MAP SENSOR SPECIFICATIONS»(ref-91121-S03969964002001030200000) table. Go to next step. MAP SENSOR SPECIFICATIONS Altitude Ft. (m) kPa Engine Stopped 0 (0) 101 1969 (600) 95 3937 (1200) 88 5906 (1800) 81 Engine Idling 23.3-38.7 Engine Suddenly Raced Increases
  9. If scan tool reading is as specified, check EGR valve and EGR passage for blockage. If scan tool reading is not as specified, check Manifold Absolute Pressure (MAP) circuit. See «DTC P0105: MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR CIRCUIT MALFUNCTION»(ref-91121-S31092339262001030200000) .
  1. Battery voltage is 10 volts or more. Code will set if solenoid coil voltage (system voltage plus 2 volts) is not detected when EGR solenoid is turned on or off.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Turn engine off. Disconnect EGR solenoid valve electrical connector. Using an ohmmeter, check resistance across solenoid valve terminals. If resistance at 68°F (20°C) is 36-44 ohms, go to next step. If resistance is not as specified, replace solenoid valve.
  2. Label and disconnect vacuum hoses from EGR solenoid valve. Connect hand vacuum pump to EGR solenoid valve fitting where Green-striped hose (Diamante) or White-striped hose (Mirage) was connected. Apply battery voltage across terminals of solenoid valve. Apply vacuum to solenoid valve. Vacuum should hold when voltage is applied to terminals. Remove battery voltage. Vacuum should now leak. If EGR solenoid valve performs as specified, go to next step. If EGR solenoid valve does not perform as specified, replace EGR solenoid valve.
  3. Turn ignition on. Check voltage between ground and EGR solenoid valve connector terminal No. 2 (Diamante) or terminal No. 1 (Mirage). If battery voltage exists, go to next step. If battery voltage does not exist, check wiring harness between MFI relay and EGR solenoid valve.
  4. Turn ignition off. Disconnect ECM connector B-108 (Diamante), or ECM connector B-40 (Mirage). Turn ignition on. Check voltage between ground and ECM connector terminal No. 6. If battery voltage exists, check ECM connector. If connector is okay, replace ECM. If battery voltage does not exist, check connectors between EGR solenoid and ECM. If connector are okay, check wiring harness between ECM and EGR solenoid.
  1. Diamante - Engine speed is 3000 RPM or more. Volume Airflow (VAF) sensor output frequency is 50-300 Hz. Intake air temperature is more than 14°F (-10°C). Atmospheric pressure is more than 11 psi (76 kPa). Closed throttle position switch is off. Engine is in closed loop control. Code will set if there is an abnormality in rear HO2S signal relative to front HO2S signal.
  2. Mirage 1.5L - Engine speed is 2600 RPM or less. Intake air temperature is 14°F (-10°C) or more. Intake air pressure is 2.9-9.2 psi (20-63 kPa) (M/T) or 3.5-9.2 psi (24-63 kPa) (A/T). Closed throttle position switch is off. Engine is in closed loop control. Vehicle speed is one MPH or more. Monitor runs 140 seconds. Code will set when there is an abnormality in rear HO2S signal relative to front HO2S signal.
  3. Mirage 1.8L - Engine speed is 3000 RPM or less. Volume Air Flow (VAF) output frequency is 69-144 Hz. Intake air temperature is 14°F (-10°C) or more. Atmospheric pressure is 11 psi (76 kPa) or more. Closed throttle position switch is off. Engine is in closed loop control. Vehicle speed is one MPH or more. Monitor runs 140 seconds. Code will set when there is an abnormality in rear HO2S signal relative to front HO2S signal.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Check exhaust manifold for cracks. Repair as necessary, then go to step 5 . If exhaust manifold is okay, go to next step.
  2. Using scan tool, read data list item No. 59 (rear heated oxygen sensor). Drive vehicle with transaxle in 2nd gear (M/T) or Low (A/T), and with wide open throttle. If voltage is 600-1000 millivolts, go to next step. If voltage is not as specified, check rear Heated Oxygen Sensor (HO2S) circuit. See «DTC P0136 & P0156: REAR HEATED OXYGEN SENSOR (HO2S) CIRCUIT MALFUNCTION»(ref-91121-S07577226732001030200000) , then go to step 5 .
  3. Using scan tool, read data list item No. 11 (front heated oxygen sensor). Monitor rear HO2S output voltage while repeatedly racing engine. If voltage is 600-1000 millivolts, go to next step. If voltage is not as specified, check front HO2S circuit. See «DTC P0130 & P0150: FRONT HEATED OXYGEN SENSOR (HO2S) CIRCUIT MALFUNCTION»(ref-91121-S38117798542001030200000) , then go to step 5 .
  4. Monitor front HO2S output voltage with engine at idle. Scan tool reading should alternate between 0-400 millivolts and 600-1000 millivolts. If voltage is as specified, replace rear HO2S. If voltage is not as specified, replace front HO2S. After repair, go to next step.
  5. Clear DTCs. Test drive vehicle following OBD-II drive cycle pattern. See CATALYTIC CONVERTER MONITOR under OBD-II DRIVE CYCLES in SELF-DIAGNOSTICS - INTRODUCTION article. Check readiness test status. If complete, test is done. If incomplete, drive catalytic converter monitor drive cycle pattern again. Check scan tool for DTCs. If DTC P0420 resets, replace catalytic convertor. Clear DTCs. Road test vehicle to verify repairs. If DTC P0420 resets, replace ECM.
  1. Engine speed is 2250 RPM or less. Intake air temperature is 14°F (-10°C) or more. Intake air pressure is 2.9-9.2 psi (20-63 kPa) (M/T) or 3.5-9.2 psi (24-63 kPa) (A/T). Closed throttle position switch is off. Engine is in closed loop control. Vehicle speed is one MPH or more. Monitor runs 140 seconds. Code will set if there is abnormality in rear Heated Oxygen Sensor (HO2S) signal relative to front HO2S.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Check exhaust manifold for cracks. If exhaust manifold is okay, go to next step.
  2. Using scan tool, read data list item No. 59 (rear heated oxygen sensor). Drive vehicle with transaxle in 2nd gear (M/T) or Low (A/T), and with wide open throttle. If voltage is 600-1000 millivolts, go to next step. If voltage is not as specified, check rear Heated Oxygen Sensor (HO2S) circuit. See «DTC P0136 & P0156: REAR HEATED OXYGEN SENSOR (HO2S) CIRCUIT MALFUNCTION»(ref-91121-S07577226732001030200000) .
  3. Using scan tool, read data list item No. 11 (front heated oxygen sensor). Monitor rear HO2S output voltage while repeatedly racing engine. If voltage is 600-1000 millivolts, go to next step. If voltage is not as specified, check front HO2S circuit. See «DTC P0130 & P0150: FRONT HEATED OXYGEN SENSOR (HO2S) CIRCUIT MALFUNCTION»(ref-91121-S38117798542001030200000) .
  4. Using scan tool, read data list item No. 11 (front heated oxygen sensor volts). Monitor front HO2S output voltage with engine at idle. Scan tool reading should alternate between 0-400 millivolts and 600-1000 millivolts. If voltage is as specified, go to next step. If voltage is not as specified, replace front HO2S.
  5. Replace rear HO2S. Clear DTCs. Road test vehicle to verify repairs. If DTC 0421 resets, replace catalytic convertor. Clear DTCs. Road test vehicle to verify repairs. If DTC 0421 resets, replace ECM.
  1. Diamante - Engine coolant temperature is 140°F (60°C) or more. Engine speed is 1600-3500 RPM. Power steering pressure switch is off. Atmospheric pressure is 11 psi (76 kPa) or more. Volumetric efficiency is 20-80 percent. Intake air temperature is 14°F (-10°C) or more. Pressure increase when EVAP purge solenoid valve and vent solenoid valve are closed is .071 psi (.480 kPa) or less. Pressure variation range is .097 psi (.667 kPa) or less. Monitor runs 50-100 seconds. Code will set when internal pressure of fuel tank has not changed more than .142 psi (.981 kPa) in 20 seconds after tank and vapor line are closed.
  2. Mirage - Intake air temperature is 86°F (30°C) or less when engine starts. At least 16 minutes have passed since engine started. Engine coolant temperature is 140°F (60°C) or more. Engine speed is 1600 RPM or more. Power steering pressure switch is in off. Atmospheric pressure is 11 psi (76 kPa) or more. Volumetric efficiency is 20-80 percent. Intake air temperature is 14°F (-10°C) or more. Pressure increase when EVAP purge solenoid valve and vent solenoid valve are closed is less than .065 psi (.451 kPa) or less. Pressure variation range is .094 psi (.647 kPa) or less. Fuel Tank Differential Pressure (FTDP) sensor output voltage is 1-4 volts. Vehicle speed is 19 MPH or more. Monitor runs 75-125 seconds. Code will set when internal pressure of fuel tank has not changed more than .122 psi (.843 kPa) in 20 seconds after tank and vapor line are closed.

Diagnostic Procedure (Diamante)

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Remove fuel cap. Push flapper in fuel filler pipe to operate On-board Fuel Vent Valve (OFLV). Install and tighten fuel cap. Remove fuel cap and ensure distance between flapper and OFLV is 1.1" (28 mm). If distance is as specified, go to next step. If distance is not as specified, replace fuel tank filler tube assembly. Go to step 24 .
  2. Disconnect and plug air filter-to-EVAP vent solenoid valve hose at air filter end. Disconnect EVAP purge solenoid valve-to-EVAP canister hose from pipe over intake manifold. Install a "T" fitting where hose was disconnected. Connect a hand-held pressure/vacuum pump to "T" fitting. Go to next step. CAUTION: DO NOT apply more vacuum or pressure than specified in following step. Applying more than specified can crack fuel tank. NOTE: Ensure fuel tank is at least 1/4 full. The lower the fuel level in fuel tank, the longer it takes to pressurize fuel system.
  3. Using scan tool, read data list item No. 73 (fuel tank differential pressure sensor). Using hand-held pressure/vacuum pump, apply 0.85 in. Hg (2.9 kPa). If scan tool reading reaches (2.9 kPa), go to next step. If reading does not reach 2.9 kPa, go to step 10 .
  4. Wait 20 seconds and read scan tool. If scan tool reading changes by .4 kPa or less, go to next step. If scan tool reading changes more than .4 kPa, go to step 21 .
  5. Disconnect EVAP canister purge hose. Connect Purge Flow Indicator (MB991700) between EVAP canister and disconnected hose. Turn engine on and allow it to reach operating temperature. Turn all lights and accessories off. Place transmission in Park or Neutral. Run engine at idle for more than 4 minutes. Increase engine RPM rapidly several time and check purge flow. If purge flow indicator reads about 2.5 SCFH (20 cm 3 /sec), go to next step. If purge flow indicator reads less than 2.5 SCFH (20 cm 3 /sec), check EVAP canister purge hose and EVAP canister port for clogging. If hose and port are okay, check EVAP purge solenoid valve. See «DTC P0443: EVAPORATIVE (EVAP) CONTROL SYSTEM PURGE CONTROL VALVE CIRCUIT MALFUNCTION»(ref-91121-S21868747062001030200000) . If solenoid is okay, replace EVAP canister. Go to step 24 .
  6. Using scan tool, read data list item No. 21 (engine coolant temperature sensor). Compare scan tool reading with temperature gauge reading. If readings are about the same, go to next step. If readings are not about the same, check Engine Coolant Temperature (ECT) circuit. See «DTC P0115: ENGINE COOLANT TEMPERATURE (ECT) CIRCUIT MALFUNCTION»(ref-91121-S11615245452001030200000) .
  7. Using a thermometer, check engine compartment ambient temperature. Using scan tool, read data list item No. 13 (intake air temperature sensor). Compare IAT sensor and thermometer readings. If readings are not about the same, check intake air temperature circuit. See «DTC P0110: INTAKE AIR TEMPERATURE (IAT) CIRCUIT MALFUNCTION»(ref-91121-S19396903782001030200000) . If readings are about the same, go to next step.
  8. Using scan tool, read data list item No. 27 (power steering pressure switch). Switch status should read ON when steering wheel is turned. If switch status is as specified, go to step 24 . If switch status is not as specified, check power steering pressure circuit. See «DTC P0551: POWER STEERING PRESSURE (PSP) SENSOR CIRCUIT RANGE/PERFORMANCE»(ref-91121-S16536123412001030200000) .
  9. Apply vacuum and perform leak check again. See steps 2 - 3 . If vacuum is maintained, check for fuel tank leak. If vacuum leaks down, replace hand pump with emission system tester continuous pressure pump. Apply continuous pressure and locate leak with ultrasonic leak detector.
  10. Remove fuel cap. Install a fuel tank filler tube adapter in place of fuel cap. Plug fuel filler tube adapter hose. Apply vacuum and perform leak check again. See steps 2 - 3 . If scan tool reading 2.9 kPa, replace fuel cap. Go to step 24 . If reading does not reach 2.9 kPa, go to next step.
  11. Disconnect hand-held pressure/vacuum pump from "T" fitting. Install an evaporative emission system tester in place of vacuum held pump and apply up to one in. Hg (3.4 kPa). Wait 2 minutes. If vacuum drops less than 0.4 in. Hg (1.4 kPa), go to step 14 . If pressure drops 0.4 in. Hg (1.4 kPa) or more, go to next step.
  12. Disconnect EVAP purge solenoid valve-to-EVAP canister hose at EVAP canister. Connect hand-held pressure/vacuum pump to hose and apply 1.8 in. Hg (6 kPa). If vacuum is not maintained, check EVAP purge solenoid valve for leak. If EVAP purge solenoid valve is okay, replace hose. Go to step 24 . If pressure is maintained, go to next step.
  13. Disconnect EVAP vent solenoid valve-to-EVAP canister hose at EVAP canister. Connect hand-held pressure/vacuum pump to hose and apply 1.8 in. Hg (6 kPa). If vacuum is not maintained, check EVAP vent solenoid valve for leak. If EVAP vent solenoid valve is okay, replace hose. Go to step 24 . If vacuum is maintained, replace EVAP canister. Go to step 24 .
  14. Ensure hoses are properly routed and connected. See VACUUM DIAGRAMS article. Install hoses as necessary and go to step 24 . If hoses are okay, go to next step.
  15. Disconnect OFLV-to-EVAP canister hose at OFLV and EVAP canister. Plug hose at OFLV end. Connect hand-held pressure/vacuum pump to hose at EVAP canister end. Apply 1.8 in. Hg (6 kPa). If vacuum is not maintained, replace hose. Go to step 24 . If vacuum is maintained, go to next step.
  16. Using scan tool, read data list item No. 73 (fuel tank differential pressure). Connect hand-held pressure/vacuum pump to OFLV. While monitoring scan tool, apply .85 in. Hg (2.9 kPa). If scan tool reading reaches 2.9 kPa, go to next step. If reading does not reach 2.9 kPa, go to step 20 .
  17. Disconnect OFLV-to-EVAP canister hose at EVAP canister. Connect hand-held pressure/vacuum pump to hose and apply 1.8 in Hg (6 kPa). If vacuum is not maintained, go to next step. If vacuum is maintained, go to step 19 .
  18. Disconnect EVAP purge solenoid valve-to-EVAP canister hose at EVAP canister. Connect hand-held pressure/vacuum pump to hose. Disconnect intake manifold plenum-to-EVAP purge solenoid valve at intake manifold plenum. Operate vacuum pump several times to apply vacuum. If vacuum leaks, replace EVAP canister. Go to step 24 . If vacuum does not leak, repair clog in hose between EVAP canister and EVAP purge solenoid valve. Go to step 24 .
  19. Disconnect EVAP canister-to-OFLV hose at OFLV. If vacuum does not leak, repair clog in hose between EVAP canister and OFLV. Go to step 24 . If vacuum leaks, check fuel tank filler tube assembly. If fuel tank filler tube assembly is okay, repair clog in hose between OFLV and fuel cut-off valve. Go to step 24 .
  20. Replace fuel tank filler tube and OFLV-to-fuel cut-off valve hose. While monitoring scan tool, apply .85 in. Hg (2.9 kPa) with hand-held pressure/vacuum pump. If scan tool reading does not reach 2.9 kPa, replace fuel tank. Go to step 24 .
  21. Remove fuel cap. Install a fuel tank filler tube adapter in place of fuel cap. Disconnect and plug air filter-to-EVAP vent solenoid valve hose at air filter. Plug fuel filler tube adapter hose. Disconnect intake manifold plenum-to-EVAP purge solenoid valve at intake manifold plenum. Install a "T" fitting between vacuum hose and intake manifold plenum. Connect hand-held pressure/vacuum pump to "T" fitting. Go to next step. CAUTION: DO NOT apply more pressure or vacuum than specified in following step. Applying more than specified can crack fuel tank. NOTE: Ensure fuel tank is at least 1/4 full. The lower the fuel level in fuel tank, the longer it takes to pressurize fuel system.
  22. Using scan tool, read data list item No. 73 (fuel tank differential pressure). Using hand-held pressure/vacuum pump, apply 0.85 in. Hg (2.9 kPa). Wait 50 seconds. If scan tool reading changes by 0.4 kPa or less, replace fuel cap. Go to step 24 . If reading changes by more than 0.4 kPa, go to next step.
  23. Disconnect hand-held pressure/vacuum pump from "T" fitting. Install an evaporative emission system tester in place of vacuum held pump and apply 0.49 psi (3.4 kPa). Using an ultrasonic leak detector, locate and repair leaks. Go to next step.
  24. Road test vehicle and attempt to duplicate conditions that caused original complaint. Recheck for DTCs. If no DTCs are displayed, test is complete.

Diagnostic Procedure (Mirage)

CAUTIONEVAP system uses very fine vacuum/pressure of .5 psi (3.4 kPa) or less. DO NOT apply excessive vacuum or pressure to system.

Note. For connector views, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article.

Note. The following test procedure requires functions available on manufacturer's MUT-II scan tool. Generic scan tools may not have the capability to carry out all tests.

Note. An improperly tightened fuel cap can cause this code to set. Check for properly installed fuel cap and a good seal between the fuel cap and fuel filler neck.

  1. If there are other DTCs, check those first. Clear DTCs using scan tool. Go to next step.
  2. Ensure fuel cap is securely tightened. Start EVAP system leak monitor test using MUT-II. Start engine. Select SYSTEM TEST and press YES key. Select EVP LEAK MON and press YES key. If KEEP TPS IN IDLE POSITION DURING THE TEST is displayed, the ECM adjusts engine speed automatically. Manual adjustment for engine speed is not needed. Keep engine idling during monitor. Go to next step. NOTE: If engine speed does not reach 2000 RPM during monitor, adjustment of speed adjusting screw may be needed. See SPEED ADJUSTING SCREW in ON-VEHICLE ADJUSTMENTS article.
  3. Item IN PROGRESS is displayed during monitor. IN PROGRESS will change from NO to YES by keeping engine speed and load within defined range. If EVAP LEAK MON. COMPLETED. TEST PASSED is then displayed, EVAP system currently is working properly. Code was probably set by improperly installed fuel cap. If EVAP LEAK MON. COMPLETED. TEST FAILED & DTCS SET is displayed, go to next step. If EVAP LEAK MON. DISCONTINUED is displayed, turn off ignition. Start monitor over. Go to step 2.
  4. Check MFI data list item No. 73 (tank pressure sensor). Observe sensor reading. Remove fuel cap. Pressure reading should now be -.5-.5 kPa. If reading is as specified, go to next step. If reading is not as specified, replace fuel tank pressure differential sensor.
  5. Remove fuel cap. Push in flapper door to operate fuel vent valve. Fuel vent valve plunger should move towards top. Reinstall and tighten fuel cap 3 clicks. Remove fuel cap and check if fuel vent valve plunger was pushed back. Distance between tip of fuel vent valve plunger and top of fuel filler neck should be 1.1" (28 mm) or more. If fuel vent valve plunger does not return, replace fuel filler neck. If fuel vent valve plunger is okay, reinstall fuel and go to next step.
  6. Find vacuum hose between canister and Purge Solenoid Valve (PSV). Disconnect hose from PSV end "E". (Scheme 87) Connect hand vacuum pump to PSV fitting. Turn ignition on. Apply vacuum and note reading. Vacuum should hold steady. Using scan tool, select actuator test item No. 8 (evaporative emission purge solenoid). This should turn PSV on and vacuum should leak down. If vacuum readings are as specified, go to next step. If vacuum readings are not as specified, go to «DTC P0443: EVAPORATIVE (EVAP) CONTROL SYSTEM PURGE CONTROL VALVE CIRCUIT MALFUNCTION»(ref-91121-S21868747062001030200000).
  7. Disconnect from canister the hose connected to Vent Solenoid Valve (VSV). Connect hand vacuum pump to that hose "F". (Scheme 87) Turn ignition on. Apply vacuum. Vacuum should leak. Using scan tool, select actuator test item No. 29 (evaporative emission ventilation solenoid). This should turn solenoid on. Apply vacuum. Vacuum should hold. If vacuum readings are as specified, go to next step. If vacuum readings are not as specified, go to «DTC P0446: EVAPORATIVE (EVAP) CONTROL SYSTEM VENT CONTROL MALFUNCTION»(ref-91121-S32262683612001030200000).
  8. Disconnect PSV to air intake plenum hose at PSV side "H". (Scheme 87) Connect hand vacuum pump to disconnected hose end. Apply vacuum and check if vacuum leaks down. If vacuum leaks down, go to next step. If vacuum holds, check for blockage in hose and intake plenum. Repair or replace as necessary, then go to next step.
  9. Plug PSV to air intake plenum hose at PSV side "H". (Scheme 87) Disconnect PSV to air intake plenum hose at air intake plenum side at "G". Connect hand vacuum pump to disconnected hose end. Apply vacuum. If vacuum holds, hose is okay. If vacuum leaks down, replace hose, and go to next step.
  10. Install mechanical vacuum gauge in purge line between PSV and canister. Before starting performance test, ensure engine coolant temperature is 176-203°F (80-95°C). Turn off all lights and accessories. Place transmission in Neutral (M/T) or Park (A/T). Select data list item No. 73 (tank pressure sensor) on scan tool to see pressure differential sensor output. Run engine at idle. Go to next step.
  11. Using locking pliers, pinch hose between PSV and intake plenum to close purge flow. Use second locking pliers to pinch closed vent hose between canister and VSV. Momentarily remove locking pliers at purge hose. Watch vacuum readings on mechanical vacuum gauge and scan tool. When vacuum reading reaches.85 in. Hg on mechanical vacuum gauge and -2.9 kPa on scan tool, pinch hose between PSV and intake plenum. Wait 20 seconds and check differential pressure reading on scan tool. Go to next step.
  12. If change in scan tool reading is.4 kPa or less, system is okay. Cause of code may have been improperly installed fuel cap. If vacuum does not build to.85 in. Hg on mechanical gauge, there is a large EVAP system leak. Test is same as test for small vacuum leak. Go to step 15. If vacuum builds to.85 in. Hg on mechanical gauge, but does not reach -2.9 kPa on scan tool, there is a blockage in system or bad pressure differential sensor. Go to next step. If vacuum builds to.85 in. Hg on mechanical gauge and -2.9 kPa on scan tool, but drops more than.1 in. Hg (.4 kPa) in 20 seconds, there is a small EVAP system leak. Go to step 15.
  13. Remove fuel cap. If vacuum reading on mechanical gauge stays the same, go to next step. If reading drops to about zero in. Hg, replace pressure differential sensor and go to step 18.
  14. Disconnect hoses No. 1 and 2. (Scheme 88) Check reading on mechanical gauge only. If vacuum drops, blockage is in fuel tank. If vacuum does not drop, disconnect hoses one by one, working from fuel tank toward engine, until blockage is found. Repair as necessary, then go to step 18.
  15. Remove fuel cap and install filler neck adapter from emission system kit in place of cap. Plug fitting on filler neck adapter. Repeat performance test. See steps 10 - 11. If EVAP system holds vacuum, replace fuel cap and go to step 18. If EVAP system does not hold vacuum, go to next step.
  16. To isolate leak, clamp off EVAP system hoses 1 and 2 as shown in illustration. (Scheme 88) Repeat performance test as described in steps 10 - 11. Use mechanical gauge reading only. If vacuum leaks down, go to next step. If vacuum reading holds, leak is in fuel tank area. Pressurize EVAP system to.49 psi (3.4 kPa). Locate leak in appropriate area using ultrasonic leak detector. Repair leak as necessary, then go to step 18.
  17. Clamp off hoses one at a time, working from fuel tank toward engine. See numbered hoses in illustration. (Scheme 88) Each time hose is clamped, repeat performance test. Repair as necessary, then go to step 18.
  18. After repairs, rerun EVAP system leak monitor test. See steps 2 - 3.

Scheme 87

Scheme 87
Scheme 87

Scheme 88

Scheme 88
Scheme 88
  1. Battery voltage is 10 volts or more. Code will set when solenoid coil surge voltage (system voltage plus 2 volts) is not detected when EVAP purge solenoid valve is turned on or off.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Remove engine cover if applicable. Label and disconnect Black-striped and Red-striped vacuum hoses from purge solenoid valve. Disconnect purge solenoid valve electrical connector. Connect hand vacuum pump to top fitting on solenoid valve fitting. Apply vacuum to solenoid valve. Vacuum should hold.
  2. Apply battery voltage across terminals of solenoid. Vacuum should bleed down when voltage is applied to terminals. Using an ohmmeter, check resistance across solenoid terminals. If resistance at 68°F (20°C) is 36-44 ohms, go to next step. If solenoid does not test as specified, replace solenoid.
  3. Check voltage between ground and purge solenoid valve connector terminal No. 2. Turn ignition on. If battery voltage exists, go to next step. If battery voltage does not exist, check wiring harness between MFI relay and purge solenoid valve connector.
  4. Turn ignition off. Disconnect ECM connector B-108 (Diamante), or ECM connector B-40 (Mirage). Turn ignition on. Check voltage between ground and ECM connector terminal No. 9 on Mirage, or ECM connector terminal No. 34 on Diamante. If battery voltage exists, check ECM connector. If connector is okay, replace ECM. If battery voltage does not exist, check purge solenoid valve connector and wiring harness between ECM and purge solenoid valve connector.
  1. Battery voltage is 10 volts or more. Code will set when solenoid coil surge voltage (system voltage plus 2 volts) is not detected when EVAP purge solenoid valve is turned on or off.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Disconnect EVAP vent solenoid valve electrical connector. Using a DVOM, check resistance across EVAP vent solenoid valve terminals. If resistance is at 68°F (20°C) is 17-21 ohms, go to next step. If resistance is not as specified, replace EVAP vent solenoid valve.
  2. Disconnect vacuum hoses from EVAP vent solenoid valve. Connect hand-held vacuum pump to top fitting on EVAP vent solenoid valve. Apply vacuum to EVAP vent solenoid valve. Vacuum should leak. Go to next step.
  3. Apply battery voltage across EVAP vent solenoid valve terminals. Vacuum should hold when voltage is applied. If EVAP vent solenoid valve performs as specified, go to next step. If EVAP vent solenoid valve does not perform as specified, replace EVAP vent solenoid valve.
  4. Turn ignition on. Check voltage between ground and EVAP vent solenoid valve connector terminal No. 2. If battery voltage exists, go to next step. If battery voltage does not exists, repair wiring harness or connectors between MFI relay and EVAP vent solenoid valve as necessary. Go to step 7 .
  5. Turn ignition off. Disconnect ECM connector B-108 on Diamante, or ECM connector B-38 on Mirage. Turn ignition on. Check voltage between ground and ECM connector terminal No. 35 on Diamante, or ECM connector terminal No. 55 on Mirage. If battery voltage exists, go to next step. If battery voltage does not exist, repair wiring harness or connectors between ECM and EVAP vent solenoid valve as necessary. Go to step 7 .
  6. Check and repair ECM connector as necessary. If connector is okay, go to next step.
  7. Test drive vehicle following OBD-II drive cycle pattern. See OTHER MONITOR under OBD-II DRIVE CYCLES in SELF-DIAGNOSTICS - INTRODUCTION article. Check scan tool for DTCs. If DTC P0446 returns, replace ECM. If no DTCs are displayed, test is complete.
  1. Diamante - Engine speed is 1500 RPM or more. Volumetric efficiency is 25-80 percent. Code will set if sensor output voltage is 4.5 volts or more, or .5 volt or less, for 10 seconds.
  2. Diamante - Closed throttle position switch is on. EVAP system pressure fluctuates .2 volt or more 20 times or more. Code will set when pressure fluctuates .2 volt or more, 20 times or more, for 15 consecutive idle operations.
  3. Mirage - Engine speed is 1600 RPM or more. Volumetric efficiency is 20-80 percent. Intake air temperature is more than 41°F (5°C). Code will set if sensor output voltage is 4 volts or more, or one volt or less, for 10 seconds.
  4. Mirage - Throttle valve is closed. Engine speed is 840 RPM or less. Vehicle speed is one MPH or less. Code will set if sudden pressure fluctuations of at least .2 volt, 25 milliseconds or more in duration, occur 20 times or more during one idling period.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Disconnect Fuel Tank Differential Pressure (FTDP) connector. Turn ignition on. Using DVOM, check voltage between ground and FTDP sensor connector terminal No. 3. Voltage should be 4.8-5.2 volts. If voltage is as specified, go to next step. If voltage is not as specified, inspect connectors and wiring harness between FTDP sensor and ECM. Repair as necessary. If connectors and wiring harness are okay, replace ECM.
  2. Using DVOM, check for continuity between ground and FTDP sensor connector terminal No. 2. If continuity exists, go to next step. If continuity does not exist, repair wiring harness as necessary.
  3. Inspect connectors and wiring harness between FTDP sensor and ECM. Repair as necessary. If connectors and wiring harness are okay, go to next step.
  4. Using scan tool, read data list item No. 73 (fuel tank differential pressure). Remove fuel cap. Scan tool pressure should be -0.5-0.5 kPa. If pressure is not as specified, go to next step. If pressure is as specified, fault is intermittent. See «INTERMITTENT DTCS»(ref-91121-S07724171582001030200000) under CIRCUIT TESTS.
  5. Remove fuel cap. Install a fuel tank filler tube adapter in place of fuel cap. Connect a hand-held pressure/vacuum pump to fuel tank filler adapter hose. Go to next step. CAUTION: DO NOT apply more than 1.0 psi (7 kPa) in following step. Applying more than specified psi can crack fuel tank. NOTE: Ensure fuel tank is at least 1/4 full. The lower the fuel level in fuel tank, the longer it takes to pressurize fuel system.
  6. Apply 1.0 psi (7 kPa). Using scan tool, read data list item No. 73 (fuel tank differential pressure). If scan tool reads more than 7 kPa, go to next step. If reading is 7 kPa or less, go to step 8 .
  7. Check On-Board Fuel Vent Valve (OFLV) for clogging. OFLV is located in fuel tank filler tube assembly. If OFLV is clogged, replace fuel tank filler tube assembly. Go to step 9 . If OFLV is okay, go to next step.
  8. Check EVAP hoses, and purge and vent solenoid valves for clogging. Repair or replace as necessary. Go to next step. If hoses and solenoids are okay, replace FTDP sensor. Go to next step.
  9. Road test vehicle and attempt to duplicate conditions that caused original complaint. Recheck for DTCs. If DTC P0450 returns, replace ECM. If no DTCs are displayed, test is complete.
CAUTIONEVAP system uses very fine vacuum/pressure of 3.4 kPa or less. Do not apply excessive vacuum or pressure to system.

Note. The following test procedure requires functions available on manufacturer's MUT-II scan tool. Generic scan tools may not have the capability to carry out these tests. Scan tool should be set in metric mode to read kPa. Tests also require mechanical vacuum gauge that reads 0-1.8 in. Hg (0-6.2 kPa).

Note. For connector views, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article.

  1. Read scan tool data list item No. 73 (tank pressure sensor). Remove fuel cap. Scan tool pressure reading should be -.5-.5 kPa. If reading is as specified, go to next step. If reading is not as specified, go to step 11.
  2. Remove fuel cap. Push in flapper door to operate fuel vent valve. Fuel vent valve plunger should move toward top. Reinstall and tighten fuel cap 3 clicks. Remove fuel cap and check if fuel vent valve plunger was pushed back. Distance between tip of fuel vent valve plunger and top of fuel filler neck should be 1.1" (28 mm) or more. If fuel vent valve plunger does not return, replace fuel filler neck. If fuel vent valve plunger is okay, reinstall fuel and go to next step.
  3. Clear DTCs using MUT-II scan tool. Ensure fuel cap is securely tightened. Start EVAP system leak monitor test. Start engine. Select SYSTEM TEST and press YES key. Select EVP LEAK MON and press YES key. If KEEP TPS IN IDLE POSITION DURING THE TEST is displayed, the ECM adjusts engine speed automatically. Manual adjustment for engine speed is not needed. Keep engine idling during monitor.
  4. Item IN PROGRESS is displayed during monitor. IN PROGRESS will change from NO to YES by keeping engine speed and load within defined range. If EVAP LEAK MON. COMPLETED. TEST PASSED is then displayed, EVAP system currently is working properly. Code was probably set by improperly installed fuel cap. If EVAP LEAK MON. COMPLETED. TEST FAILED & DTCS SET is displayed, go to next step. If EVAP LEAK MON. DISCONTINUED is displayed, turn off ignition. Start monitor over. Go to step 3.
  5. Disconnect PSV to air intake plenum hose at PSV side "H". (Scheme 87) Connect hand vacuum pump to disconnected hose end. Apply vacuum and check if vacuum leaks down. If vacuum leaks down, go to next step. If vacuum holds, check for blockage in hose and intake plenum. Repair or replace as necessary, then go to step 7.
  6. Plug PSV to air intake plenum hose at PSV side "H". (Scheme 87) Disconnect PSV to air intake plenum hose at air intake plenum side at "G". Connect hand vacuum pump to disconnected hose end. Apply vacuum. If vacuum holds, hose is okay. If vacuum leaks down, replace hose. Go to next step.
  7. Install 0-1.8 in. Hg (0-6.2 kPa) mechanical vacuum gauge in purge line between PSV and canister. Before starting performance test, ensure engine coolant temperature is 176-194°F (80-90°C). Turn off all lights and accessories. Put transmission in Neutral (M/T) or Park (A/T). Select data list item No. 73 (tank pressure sensor) on scan tool. Run engine at idle. Go to next step.
  8. Using locking pliers, pinch hose between PSV and intake plenum to close purge flow. Use second locking pliers to pinch closed vent hose between canister and VSV. Momentarily remove locking pliers at purge hose. Watch vacuum readings on mechanical vacuum gauge and scan tool. When vacuum reading reaches.85 in. Hg on mechanical vacuum gauge and -2.9 kPa on scan tool, pinch hose between PSV and intake plenum again. Wait 20 seconds and check differential pressure reading on scan tool. Go to next step.
  9. If change in scan tool reading is.4 kPa or less, system is okay. Cause of code may have been improperly installed fuel cap. If vacuum does not build to.85 in. Hg on mechanical gauge, there is a large EVAP system leak. Test is same as test for small vacuum leak. Go to step 15. If vacuum builds to.85 in. Hg on mechanical gauge, but does not reach -2.9 kPa on scan tool, there is a blockage in system or bad pressure differential sensor. Go to next step. If vacuum builds to.85 in. Hg on mechanical gauge and -2.9 kPa on scan tool, but drops more than.1 in. Hg (.4 kPa) in 20 seconds, there is a small EVAP system leak. Go to step 15.
  10. Remove fuel cap. If vacuum reading on mechanical gauge stays the same, go to step 13. If reading drops to about zero in. Hg, go to next step.
  11. Remove floor carpet and floor cover. Remove tank pressure differential sensor. Leave electrical connector attached. Connect hand vacuum pump and 0-1.8 in. Hg (0-6.2 kPa) mechanical vacuum gauge to tank pressure differential sensor. Go to next step.
  12. Turn ignition on. Using scan tool, check data list item No. 73 (tank pressure sensor) while applying vacuum. With no vacuum applied, scan tool should read zero kPa and output voltage should be 2.4-2.6 volts. With 1.5 in. Hg (5 kPa) vacuum applied, scan tool should read -5 kPa and output voltage should be.9-1.1 volts. If tank pressure differential sensor is as specified, problem is intermittent. See «INTERMITTENT DTCS»(ref-91121-S07724171582001030200000) under CIRCUIT TESTS. If tank pressure differential sensor is not as specified, go to step 19.
  13. Disconnect hoses No. 1 and 2. (Scheme 88) Check reading on mechanical gauge only. If vacuum drops, go to next step. If vacuum does not drop, disconnect hoses one by one, working from fuel tank toward engine, until blockage is found. Repair as necessary, then go to step 24.
  14. Remove fuel tank. Remove FTDP sensor. Leave electrical connector attached. Connect a 0-1.8 in. Hg (0-6.2 kPa) hand vacuum pump to FTDP sensor. Turn ignition on. Check scan tool data list item No. 73 (tank pressure sensor). When no vacuum is applied, FTDP sensor output voltage should be 2.4-2.6 volts and scan tool should read 0 kPa. When 1.5 in. Hg (5 kPa) of vacuum is applied, FTDP sensor output voltage should be.9-1.1 volt and scan too should read -5 kPa. If values are as specified, problem is intermittent. See «INTERMITTENT DTCS»(ref-91121-S07724171582001030200000) under CIRCUIT TESTS. If values are not as specified, go to step 19.
  15. Remove fuel cap. Install filler neck adapter from emission system kit in place of cap. Plug fitting on filler neck adapter. Repeat performance test. See step 8. If EVAP system holds vacuum, replace fuel cap and go to step 24. If EVAP system does not hold vacuum, go to next step.
  16. Clamp off EVAP system hoses 1 and 2. (Scheme 88) Go to next step.
  17. Repeat performance test. See step 8. Read mechanical gauge only. If vacuum leaks down, go to next step. If vacuum reading holds, leak is in fuel tank area. Pressurize EVAP system to.49 psi (3.4 kPa). Locate leak in appropriate area using ultrasonic leak detector. Repair leak as necessary, then go to step 24.
  18. Clamp off hoses one at a time, working from fuel tank toward engine. See numbered hoses in illustration. (Scheme 88) Each time hose is clamped, repeat performance test. Repair as necessary, then go to step 24.
  19. Disconnect Fuel Tank Differential Pressure (FTDP) sensor 3-pin connector. Turn ignition switch on. Measure voltage between ground and FTDP sensor connector (harness side) terminal No. 3. If voltage is 4.8-5.2 volts, go to next step. If voltage is not 4.8-5.2 volts, check for short or open in wire between FTDP sensor and ECM. Repair as necessary, then go to step 24.
  20. Turn ignition off. Check continuity between ground and FTDP sensor connector (harness side) terminal No. 2. If resistance is zero ohms, go to next step. If resistance is more than zero ohms repair open or high resistance in wire between FTDP sensor and ECM, then go to step 24.
  21. Disconnect ECM connector B-38. Check continuity of wire between FTDP sensor and ECM connector terminal No. 61. If resistance is zero ohms, go to next step. If resistance is more than zero ohms repair wire between FTDP sensor and ECM, then go to step 24.
  22. Check FTDP sensor connector and ECM connectors. Repair as necessary. Then go to next step. If connectors are okay, replace ECM, then go to step 24.
  23. Reinstall removed parts. Repeat performance test. See steps 3 - 4. If scan tool reading still does not reach -2.9 kPa, replace ECM, then go to step 24.
  24. After repair, reconnect hoses. Repeat EVAP system leak monitor. See steps 3 - 4.
  1. Diamante - Engine coolant temperature is 140°F (60°C) or more. Engine speed is 1600-3500 RPM. Power steering pressure switch is in OFF position. Atmospheric pressure is 11 psi (76 kPa) or more. Volumetric efficiency if 20-80 percent. Intake air temperature is 14°F (-10°C) or more. Pressure increase when EVAP purge solenoid valve and vent solenoid valve are closed is .071 psi (.480 kPa) or less. Pressure variation range is .097 psi (.667 kPa) or less. Monitor runs 50-100 seconds. When fuel tank and vapor line are closed, code will set when 50 seconds after EVAP purge solenoid valve is driven, pressure change is less than .045 psi (.324 kPa).
  2. Mirage - At least 16 minutes have passed since engine started. Intake air temperature was 86°F (30°C) or less when engine started. Engine coolant temperature is 140°F (60°C) or more. Engine speed is 1600 RPM or more. Power steering pressure switch is in OFF position. Atmospheric pressure is 11 psi (76 kPa) or more. Volumetric efficiency is 20-80 percent. Intake air temperature is more than 41°F (5°C). Pressure increase when EVAP purge solenoid valve and vent solenoid valve are closed is less than .065 psi (.451 kPa). Pressure variation range is .094 psi (.647 kPa) or less. At least 20 seconds have passed since pressure fluctuation detection started. Fuel Tank Differential Pressure (FTDP) sensor output voltage is 1-4 volts. Vehicle speed is 19 MPH or more. Monitor runs 75-125 seconds. Code will set when fuel tank pressure change is more than .122 psi (.843 kPa) in 20 seconds after fuel tank and vapor line are closed.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Remove fuel cap. Push fuel pipe flapper to operate On-board Fuel Vent Valve (OFLV). Install and tighten fuel cap. Remove fuel cap and ensure distance between filler tube and OFLV flapper is 1.1" (28 mm). If distance is as specified, go to next step. If distance is not as specified, replace fuel tank filler tube assembly. Go to step 24 .
  2. Disconnect and plug air filter-to-EVAP vent solenoid valve hose at air filter. Disconnect intake manifold plenum-to-EVAP purge solenoid valve at intake manifold plenum. Install a "T" fitting between vacuum hose and intake manifold plenum. Connect a hand-held pressure/vacuum pump to "T" fitting. Go to next step. CAUTION: DO NOT apply more than 0.57 psi (3.9 kPa) in following step. Applying more than specified psi can crack fuel tank. NOTE: Ensure fuel tank is at least 1/4 full. The lower the fuel level in fuel tank, the longer it takes to pressurize fuel system.
  3. Using scan tool, read data list item No. 73 (fuel tank differential pressure sensor). Using hand-held pressure/vacuum pump, apply 0.42 psi (2.9 kPa). If scan tool reading reaches 0.42 psi (2.9 kPa), go to next step. If reading does not reach 0.42 psi (2.9 kPa), go to step 9 .
  4. Wait 20 seconds and read scan tool. If scan tool reading increases .4 kPa or less, go to next step. If scan tool reading increases more than .4 kPa, go to step 21 .
  5. Disconnect EVAP canister purge hose. Connect Purge Flow Indicator (MB991700) between EVAP canister and disconnected hose. Turn engine on and allow it to reach operating temperature. Turn all lights and accessories off. Place transmission in Park or Neutral. Observe purge flow indicator while increasing engine RPM several times. If purge flow indicator reads less than 2.5 SCFH (20 cm 3 /sec), check EVAP canister purge hose and EVAP canister port for clogging. If hose and port are okay, check EVAP purge solenoid valve. See «DTC P0443: EVAPORATIVE (EVAP) CONTROL SYSTEM PURGE CONTROL VALVE CIRCUIT MALFUNCTION»(ref-91121-S21868747062001030200000) . If solenoid is okay, replace EVAP canister. Go to step 24 .
  6. Using scan tool, read data list item No. 21 (engine coolant temperature sensor). Compare scan tool reading with temperature gauge reading. If readings are about the same, go to next step. If readings are not about the same, check Engine Coolant Temperature (ECT) circuit. See «DTC P0115: ENGINE COOLANT TEMPERATURE (ECT) CIRCUIT MALFUNCTION»(ref-91121-S11615245452001030200000) .
  7. Using a thermometer, check engine compartment ambient temperature. Using scan tool, read data list item No. 13 (intake air temperature sensor). Compare IAT sensor and thermometer readings. If readings are not about the same, check intake air temperature circuit. See «DTC P0110: INTAKE AIR TEMPERATURE (IAT) CIRCUIT MALFUNCTION»(ref-91121-S19396903782001030200000) . If readings are about the same, go to next step.
  8. Using scan tool, read data list item No. 27 (power steering pressure switch). Switch status should read ON when steering wheel is turned. If switch status is as specified, go to step 24 . If switch status is not as specified, check power steering pressure circuit. See «DTC P0551: POWER STEERING PRESSURE (PSP) SENSOR CIRCUIT RANGE/PERFORMANCE»(ref-91121-S16536123412001030200000) .
  9. Disconnect vapor hose from fuel cut-off valve and plug hose end. Disconnect from pipe over air intake plenum the purge hose connected between EVAP purge solenoid valve and EVAP canister. Use "T" fitting to connect hand vacuum pump between hose and pipe. Apply 1.7 in. Hg (6 kPa) vacuum. If vacuum holds, check for leakage in fuel tank area. If vacuum leaks, go to next step.
  10. Replace hand pump with continuous vacuum source such as emission system tester. While applying continuous pressure, use ultrasonic leak detector to pinpoint leak. Repair as necessary, then retest.
  11. Disconnect hand-held pressure/vacuum pump from "T" fitting. Install an evaporative emission system tester in place of vacuum held pump and apply 0.49 psi (3.4 kPa). Wait 2 minutes. If pressure drops less than 0.20 psi (1.4 kPa), go to next step. If pressure drops 0.29 psi (2.0 kPa) or more, go to step 14 .
  12. Disconnect EVAP purge solenoid valve-to-EVAP canister hose at EVAP canister. Connect hand-held pressure/vacuum pump to hose and apply 0.9 psi (6.2 kPa). If pressure is not maintained, check EVAP purge solenoid valve for leak. If EVAP purge solenoid valve is okay, replace hose. Go to step 24 . If pressure is maintained, go to next step.
  13. Disconnect EVAP vent solenoid valve-to-EVAP canister hose at EVAP canister. Connect hand-held pressure/vacuum pump to hose and apply 0.9 psi (6.2 kPa). If pressure is not maintained, check EVAP vent solenoid valve for leak. If EVAP vent solenoid valve is okay, replace hose. Go to step 24 . If pressure is maintained, replace EVAP canister. Go to step 24 .
  14. Ensure hoses are properly routed and connected. See VACUUM DIAGRAMS article. Install hoses as necessary and go to step 24 . If hoses are okay, go to next step.
  15. Disconnect OFLV-to-EVAP canister hose at OFLV and EVAP canister. Plug hose at OFLV end. Connect hand-held pressure/vacuum pump to hose at EVAP canister end. Apply 0.9 psi (6.2 kPa). If pressure is not maintained, replace hose. Go to step 24 . If pressure is maintained, go to next step.
  16. Using scan tool, read data list item No. 73 (fuel tank differential pressure). Connect hand-held pressure/vacuum pump to OFLV. While monitoring scan tool, apply 0.42 psi (2.9 kPa). If scan tool reading reaches 2.9 kPa, go to next step. If reading does not reach 2.9 kPa, go to step 20 .
  17. Disconnect OFLV-to-EVAP canister hose at EVAP canister. Connect hand-held pressure/vacuum pump to hose and apply 0.9 psi (6.2 kPa). If pressure is not maintained, go to next step. If pressure is maintained, go to step 19 .
  18. Disconnect EVAP purge solenoid valve-to-EVAP canister hose at EVAP canister. Connect hand-held pressure/vacuum pump to hose. Disconnect intake manifold plenum-to-EVAP purge solenoid valve at intake manifold plenum. Operate vacuum pump several times to apply vacuum. If vacuum leaks, replace EVAP canister. Go to step 24 . If vacuum does not leak, repair clog in hose between EVAP canister and EVAP purge solenoid valve. Go to step 24 .
  19. Disconnect EVAP canister-to-OFLV hose at OFLV. If vacuum does not leak, repair clog in hose between EVAP canister and OFLV. Go to step 24 . If vacuum leaks, check fuel tank filler tube assembly. If fuel tank filler tube assembly is okay, repair clog in hose between OFLV and fuel cut-off valve. Go to step 24 .
  20. Replace fuel tank filler tube and OFLV-to-fuel cut-off valve hose. While monitoring scan tool, apply 0.42 psi (2.9 kPa) with hand-held pressure/vacuum pump. If scan tool reading does not reach 2.9 kPa, replace fuel tank. Go to step 24 .
  21. Remove fuel cap. Install a fuel tank filler tube adapter in place of fuel cap. Disconnect and plug air filter-to-EVAP vent solenoid valve hose at air filter. Plug fuel filler tube adapter hose. Disconnect intake manifold plenum-to-EVAP purge solenoid valve at intake manifold plenum. Install a "T" fitting between vacuum hose and intake manifold plenum. Connect hand-held pressure/vacuum pump to "T" fitting. Go to next step. CAUTION: DO NOT apply more than 0.57 psi (3.9 kPa) in following step. Applying more than specified psi can crack fuel tank. NOTE: Ensure fuel tank is at least 1/4 full. The lower the fuel level in fuel tank, the longer it takes to pressurize fuel system.
  22. Using scan tool, read data list item No. 73 (fuel tank differential pressure). Using hand-held pressure/vacuum pump, apply 0.42 psi (2.9 kPa). If scan tool reading increases 0.06 psi (.4 kPa) or less, replace fuel cap. Go to step 24 . If reading increases more than 0.06 psi (.4 kPa), go to next step.
  23. Disconnect hand-held pressure/vacuum pump from "T" fitting. Install an evaporative emission system tester in place of vacuum held pump and apply 0.49 psi (3.4 kPa). Using an ultrasonic leak detector, locate and repair leaks. Go to next step.
  24. Road test vehicle and attempt to duplicate conditions that caused original complaint. Recheck for DTCs. If no DTCs are displayed, test is complete.
CAUTIONEVAP system uses very fine vacuum/pressure of .5 psi (3.4 kPa) or less. D) NOT apply excessive vacuum or pressure to system.

Note. The following test procedure requires functions available on manufacturer's MUT-II scan tool. Generic scan tools may not have the capability to carry out all tests.

Note. An improperly tightened fuel cap can cause this code to set. Check for properly installed fuel cap and a good seal between the fuel cap and fuel filler neck.

Note. For connector views, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article.

  1. If there are other DTCs, check those first. Clear DTCs using scan tool. Go to next step.
  2. Ensure fuel cap is securely tightened. Start EVAP system leak monitor test using MUT-II. Start engine. Select SYSTEM TEST and press YES key. Select EVP LEAK MON and press YES key. If KEEP TPS IN IDLE POSITION DURING THE TEST is displayed, Engine Control Module (ECM) adjusts engine speed automatically. Manual adjustment for engine speed is not needed. Keep engine idling during monitor. NOTE: If engine speed does not reach 2000 RPM during monitor, adjustment of speed adjusting screw may be needed. See FIXED SPEED ADJUSTING SCREW in ON-VEHICLE ADJUSTMENTS article.
  3. Item IN PROGRESS is displayed during monitor. IN PROGRESS will change from NO to YES by keeping engine speed and load within defined range. If EVAP LEAK MON. COMPLETED. TEST PASSED is then displayed, EVAP system currently is working properly. Code was probably set by improperly installed fuel cap. If EVAP LEAK MON. COMPLETED. TEST FAILED & DTCS SET is displayed, go to next step. If EVAP LEAK MON. DISCONTINUED is displayed, turn off ignition. Start monitor over. Go to step 2.
  4. Check scan tool data list item No. 73 (tank pressure sensor). Remove fuel cap. Scan tool pressure reading should be -.5-.5 kPa. If reading is as specified, go to next step. If reading is not as specified, replace fuel tank pressure differential sensor, then go to step 18.
  5. Remove fuel cap. Push in flapper door to operate fuel vent valve. Fuel vent valve plunger should move toward top. Reinstall and tighten fuel cap 3 clicks. Remove fuel cap and check if fuel vent valve plunger was pushed back. Distance between tip of fuel vent valve plunger and top of fuel filler neck should be 1.1" (28 mm) or more. If fuel vent valve plunger does not return, replace fuel filler neck. If fuel vent valve plunger is okay, reinstall fuel cap and go to next step.
  6. Find vacuum hose between canister and Purge Valve Solenoid (PSV). Disconnect hose from PSV end "E". (Scheme 87) Connect hand vacuum pump to PSV fitting. Turn ignition on. Apply vacuum and note reading. Vacuum should hold steady. Using MUT-II scan tool, select actuator test item No. 8 (evaporative emission purge solenoid). This should turn PSV on and vacuum should leak down. If vacuum readings are as specified, go to next step. If vacuum readings are not as specified, go to «DTC P0443: EVAPORATIVE (EVAP) CONTROL SYSTEM PURGE CONTROL VALVE CIRCUIT MALFUNCTION»(ref-91121-S21868747062001030200000).
  7. Disconnect canister hose connected to Vent Solenoid Valve (VSV). Connect hand vacuum pump to hose "F". (Scheme 87) Turn ignition on. Apply vacuum. Vacuum should leak. Using scan tool, select actuator test item No. 29 (evaporative emission ventilation solenoid). This should turn solenoid on. Apply vacuum. Vacuum should hold. If vacuum readings are as specified, go to next step. If vacuum readings are not as specified, go to «DTC P0446: EVAPORATIVE (EVAP) CONTROL SYSTEM VENT CONTROL MALFUNCTION»(ref-91121-S32262683612001030200000).
  8. Disconnect PSV-to-air intake plenum hose at PSV side "H". (Scheme 87) Connect hand vacuum pump to disconnected hose end. Apply vacuum and check if vacuum leaks down. If vacuum leaks down, go to next step. If vacuum holds, check for blockage in hose and intake plenum. Repair or replace as necessary, then go to next step.
  9. Plug PSV-to-air intake plenum hose at PSV side "H". (Scheme 87) Disconnect PSV to air intake plenum hose at air intake plenum side at "G". Connect hand vacuum pump to disconnected hose. Apply vacuum. If vacuum holds, hose is okay. If vacuum leaks down, replace hose. Then go to next step.
  10. Install mechanical 0-1.8 in. Hg (0-6.2 kPa) vacuum gauge in purge line between PSV and canister. Before starting performance test, ensure engine coolant temperature is 176-194°F (80-90°C). Turn off all lights and accessories. Put transmission in Neutral (M/T) or Park (A/T). Select data list item No. 73 (tank pressure sensor) on scan tool. Run engine at idle. Go to next step.
  11. Using locking pliers, pinch hose between PSV and intake plenum to close purge flow. Use second locking pliers to pinch closed vent hose between canister and VSV. Momentarily remove locking pliers at purge hose. Watch vacuum readings on mechanical vacuum gauge and scan tool. When vacuum reading reaches.85 in. Hg (2.9 kPa) on mechanical vacuum gauge and -2.9 kPa on scan tool, pinch hose between PSV and intake plenum. Wait 20 seconds and check differential pressure reading on scan tool. Go to next step.
  12. If change in scan tool reading is.4 kPa or less, system is okay. Cause of code may have been improperly installed fuel cap. If vacuum does not build to.85 in. Hg (2.9 kPa) on mechanical gauge, there is a large EVAP system leak. Test is same as test for small vacuum leak. Go to step 15. If vacuum builds to.85 in. Hg (2.9 kPa) on mechanical gauge, but does not reach -2.9 kPa on scan tool, there is a blockage in system or bad pressure differential sensor. Go to step 13. If vacuum builds to.85 in. Hg (2.9 kPa) on mechanical gauge and -2.9 kPa on scan tool, but drops more than.1 in. Hg (.4 kPa) in 20 seconds, there is a small EVAP system leak. Go to step 15.
  13. Remove fuel cap. If vacuum reading on mechanical gauge stays the same, go next step. If reading drops to about zero in. Hg, replace pressure differential sensor, then go to step 18.
  14. Disconnect hoses No. 1 and 2. (Scheme 88) Check reading on mechanical gauge only. If vacuum drops, blockage is in fuel tank. If vacuum does not drop, disconnect hoses one by one, working from fuel tank toward engine, until blockage is found. Repair as necessary, then go to step 18.
  15. Remove fuel cap and install filler neck adapter from emission system kit in place of cap. Plug fitting on filler neck adapter. Repeat performance test. See steps 10 - 11. If EVAP system holds vacuum, replace fuel cap and go to step 18. If EVAP system does not hold vacuum, go to next step.
  16. To isolate leak, clamp off EVAP system hoses No. 1 and 2. (Scheme 88) Repeat performance test. See steps 10 - 11. Use mechanical gauge reading only. If vacuum leaks down, go to next step. If vacuum reading holds, leak is in fuel tank area. Pressurize EVAP system to.49 psi (3.4 kPa). Locate for leak in appropriate area using ultrasonic leak detector. Repair leak as necessary, then go to step 18.
  17. Clamp off hoses one at a time, working from fuel tank toward engine. See numbered hoses in illustration. (Scheme 88) Each time hose is clamped, repeat performance test. Repair as necessary, then go to step 18.
  18. After repairs, rerun EVAP system leak monitor test. See steps 2 - 3.
  1. Engine speed is 3000 RPM or more. Volumetric efficiency is more than 70 percent. Closed throttle position switch is off. Code will set when sensor output voltage has not changed for 4 seconds (Diamante) or 2 seconds (Mirage).

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Remove VSS from transmission. Connect battery, resistor (3-10 ohms) and voltmeter to indicated terminals. (Scheme 89) Spin VSS shaft. Ensure voltage pulses 4 times per speedometer shaft revolution. If voltage is not as specified, replace VSS. If voltage is as specified, go to next step.
  2. Turn ignition on. Check voltage between ground and VSS connector terminal No. 1. If batter voltage exists, go to next step. If battery voltage does not exist, check connectors and wiring harness between VSS and ignition switch.
  3. Check voltage between ground and VSS connector terminal No. 3. If voltage is 4.8-5.2 volts, go to next step. If voltage is not as specified, check connectors and wiring harness between VSS and ECM. If connectors and wiring harness are okay, replace ECM.
  4. Check continuity between ground and VSS connector terminal No. 2. If continuity exists, go to next step. If continuity does not exist, check connectors and wiring harness between ground and VSS.
  5. Check VSS connector. Repair connector as necessary. Clear DTCs. Road test vehicle to verify repairs. If DTC P0500 resets, replace ECM.

Scheme 89

Scheme 89
Scheme 89
  1. Engine is in closed loop idle speed control. Code will set when idle speed is more than target idle speed by 300 RPM or more for 10 seconds.
  2. Engine is in closed loop idle speed control. During previous operation, maximum ambient temperature was less than 113°F (45°C). Engine coolant temperature is more than 176°F (80°C). Battery voltage is more than 10 volts. Intake air temperature is more than 14°F (-10°C). Atmospheric pressure is more than 11 psi (76 kPa). Code will set when idle speed is more than target idle speed by more than 200 RPM for 10 seconds.
  3. Engine is in closed loop idle speed control. Power steering switch is in OFF position. Volumetric efficiency is less than 40 percent. Intake air temperature is more than 14°F (-10°C). Atmospheric pressure is more than 11 psi (76 kPa). Code will set when idle speed is more than target idle speed by 100 RPM for 10 seconds.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Ensure engine coolant temperature is less than 68°F (20°C). Using a stethoscope, listen for operating sound of Idle Air Control (IAC) motor when ignition switch is placed in ON position (engine off). If operating sound can be heard, go to next step. If no operating sound can be heard, check IAC motor drive circuit. If IAC motor drive circuit is okay, replace IAC motor.
  2. Turn ignition off. Disconnect IAC motor connector. Check resistance between IAC motor connector (component side) terminal No. 2 and either terminal No. 1 or 3. Also, check resistance between IAC motor connector terminal No. 5 and either terminal No. 6 or 4. Resistances at 68°F (20°C) should be 28-33 ohms. If any resistance is not as specified, replace IAC motor. If all resistances are as specified, go to next step.
  3. Turn ignition on. Check voltage between ground and IAC motor connector terminal No. 2, and between ground and terminal No. 5. If battery voltage exists, go to next step. If battery voltage does not exist, check wiring harness between MFI relay and IAC motor connector.
  4. Turn ignition off. Disconnect ECM connector B-108 on Diamante, or ECM connector B-40 on Mirage. Turn ignition on. Check voltage between ground and ECM connector terminals No. 4, 5, 17 and 18 on Mirage, or ECM terminals No. 14, 15, 28 and 29 on Diamante. If battery voltage exists, check ECM connector. If connector is okay, replace ECM. If battery voltage does not exist, check IAC motor connector and wiring harness between ECM and IAC motor connector.
  1. TP sensor output voltage is more than 2 volts. Code will set if closed throttle position switch is on.
  2. Vehicle is repeatedly driven and stopped more than 15 times. Drive is when engine speed is more than 1500 RPM for more than 2 seconds. Stopping is when vehicle speed is one MPH or less. Code will set when closed throttle position switch continues to be off.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Disconnect TP sensor connector. Check continuity between TP sensor connector terminals No. 1 and 2 on Diamante without traction control, terminals No. 1 and 3 on Diamante with traction control, or terminals No. 3 and 4 on Mirage. Continuity should exist with throttle at idle. Continuity should not exist when throttle is opened. If continuity is as specified, go to next step. If continuity is not as specified, replace TP sensor.
  2. Turn ignition on. Check voltage between ground and TP sensor connector terminal No. 2 on Diamante without traction control, terminal No. 1 on Diamante with traction control, or terminal No. 3 on Mirage. Voltage should be 4 volts or more. Check continuity between ground and TP sensor connector terminal No. 1 on Diamante without traction control, terminal No. 4 on Diamante with traction control, or terminal No. 4 on Mirage. If voltage is as specified and continuity exists, check TP sensor connector. If connector is okay, replace ECM. If voltage is not as specified or continuity does not exist, check ECM connector and wiring harness between ECM and TP sensor connector. If connector and wiring are okay, replace ECM.
  1. Diamante - Engine coolant temperature is more than 50°F (10°C). Vehicle is repeatedly driven and stopped more than 10 times. Drive is when engine speed is more than 2500 RPM and volumetric efficiency is more than 55 percent for more than 2 seconds. Stopping is when engine speed is 800 RPM or less. Code will set when power steering switch stays on.
  2. Mirage - Intake air temperature is 14°F (-10°C) or more. Barometric pressure is 11 psi (76 kPa) or more. Engine coolant temperature is 86°F (30°C) or more. Vehicle is repeatedly driven and stopped 10 times or more. Driving is when engine speed is 2500 RPM or more and vehicle speed is 3 MPH for 4 seconds or more. Stopping is when vehicle speed is one MPH or less. Code will set if power steering pressure switch stays on.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Disconnect pressure hose from oil pump. (Scheme 90) Install Adapter (MB990993 or MB991217) on oil pump. Install Adapter (MB990994) on disconnected hose. Connect Pressure Gauge (MB990662) and shutoff valve between adapters. Open shutoff valve. Bleed steering hydraulic system. See HYDRAULIC SYSTEM BLEEDING in appropriate POWER STEERING article in STEERING.
  2. Install a thermometer in fluid reservoir. Start engine and allow it to idle. Turn steering wheel several times until fluid temperature reaches 122-140°F (50-60°C). Disconnect PSP switch connector. Install a DVOM between ground and PSP switch terminal. (Scheme 90) Note continuity reading on DVOM. Go to next step.
  3. With engine idling, gradually close shutoff valve to increase power steering system pressure. Check pressure when PSP switch is actuated by watching for a change in continuity. PSP switch should be actuated when pressure is 483-625 psi on Diamante, or 213-285 psi on Mirage. Gradually open shutoff valve to decrease pressure. Check pressure when PSP switch is de-actuated. PSP switch should de-actuate at 255-341 psi on Diamante, or 100-185 psi on Mirage. Turn engine off. If PSP operates as specified, go to next step. If PSP does not operate as specified, replace PSP switch.
  4. Disconnect PSP switch connector. Turn ignition on. Using DVOM, check voltage between ground and PSP switch connector terminal No. 1. If battery voltage exists, inspect PSP switch connector for damage. Repair or replace PSP switch connector as necessary. If PSP switch connector is okay, replace ECM. If battery voltage does not exist, go to next step.
  5. Check wiring harness between PSP switch and ECM. Repair wiring harness as necessary. If wiring harness is okay, go to next step.
  6. Inspect ECM connector for damage. Repair or replace connector as necessary. If connector is okay, replace ECM.

Scheme 90

Scheme 90
Scheme 90
  1. Code will set when park/neutral position switch fail signal is input to ECM from Transaxle Control Module (TCM).

DTC P0705 is related to Electronic Automatic Transaxle (EATX) diagnostics. For diagnostic procedure, see appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS.

  1. Engine speed is 500 RPM or more. Shift lever is in any position other than Neutral. Code will set when oil temperature sensor failure signal is input to ECM from Transaxle Control Module (TCM).

DTC P0710 is related to Electronic Automatic Transaxle (EATX) diagnostics. For diagnostic procedure, see appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS.

  1. Input shaft speed sensor fail signal is input to ECM from Transaxle Control Module (TCM).

DTC P0715 is related to Electronic Automatic Transaxle (EATX) diagnostics. For diagnostic procedure, see appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS.

  1. Output shaft speed sensor fail signal is input to ECM from Transaxle Control Module (TCM).

DTC P0720 is related to Electronic Automatic Transaxle (EATX) diagnostics. For diagnostic procedure, see appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS.

  1. Crankshaft Position (CKP) sensor fail signal is input to ECM from Transaxle Control Module (TCM).

DTC P0725 is related to Electronic Automatic Transaxle (EATX) diagnostics. For diagnostic procedure, see appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS.

  1. Torque converter clutch and related systems fail signal is input to ECM from Transaxle Control Module (TCM).

DTC P0740 is related to Electronic Automatic Transaxle (EATX) diagnostics. For diagnostic procedure, see appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS.

  1. Low-reverse solenoid failure signal is input to ECM from Transaxle Control Module (TCM).

DTC P0750 is related to Electronic Automatic Transaxle (EATX) diagnostics. For diagnostic procedure, see appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS.

  1. Underdrive solenoid fail signal is input to ECM from Transaxle Control Module (TCM).

DTC P0755 is related to Electronic Automatic Transaxle (EATX) diagnostics. For diagnostic procedure, see appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS.

  1. Second solenoid fail signal is input to ECM from Transaxle Control Module (TCM).

DTC P0760 is related to Electronic Automatic Transaxle (EATX) diagnostics. For diagnostic procedure, see appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS.

  1. Overdrive solenoid fail signal is input to ECM from Transaxle Control Module (TCM).

DTC P0765 is related to Electronic Automatic Transaxle (EATX) diagnostics. For diagnostic procedure, see appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS.

  1. Ignition switch is in ON position. At least 60 seconds have passed since ignition switch was turned on or engine started. Battery voltage is 10 volts or more. Forced actuation by means of MUT-II scan tool is not being carried out. Code will set when solenoid coil surge voltage (system voltage plus 2 volts) is not detected when solenoid valve is turned on or off.
  1. Disconnect electrical connector from vacuum control solenoid valve. Check resistance across vacuum control solenoid valve terminals. Resistance at 68°F (20°C) should be 36-44 ohms. If resistance is as specified, go to next step. If resistance is not as specified, replace vacuum control solenoid valve.
  2. Disconnect Blue-striped and Green-striped hoses from vacuum control solenoid valve. Connect hand vacuum pump to vacuum control solenoid valve fitting where Blue-striped hose was attached. Apply vacuum. Vacuum should hold. Then apply battery voltage across vacuum control solenoid valve terminals. Vacuum should leak down. If vacuum control solenoid valve performs as specified, go to next step. If vacuum control solenoid valve does not perform as specified, replace vacuum control solenoid valve.
  3. Turn ignition on. Check voltage between ground and vacuum control solenoid valve connector terminal No. 2. If battery voltage exists, go to next step. If battery voltage does not exist, check wiring harness between vacuum control solenoid valve and control relay.
  4. Turn ignition off. Disconnect ECM connector B-108. Check voltage between ground and ECM connector B-108 terminal No. 30. If battery voltage does not exist, check wire between vacuum control solenoid valve and ECM. If battery voltage exists, check ECM connector. If connector is okay, replace ECM.
  1. Ignition switch is in ON position. At least 60 seconds have passed since ignition switch was turned on or engine started. Battery voltage is 10 volts or more. Forced actuation by means of MUT-II scan tool is not being carried out. Code will set when solenoid coil surge voltage (system voltage plus 2 volts) is not detected when solenoid valve is turned on or off.
  1. Disconnect ventilation control solenoid valve electrical connector. Check resistance across ventilation control solenoid valve terminals. Resistance at 68°F (20°C) should be 36-44 ohms. If resistance is as specified, go to next step. If resistance is not as specified, replace ventilation control solenoid valve.
  2. Disconnect Green-striped vacuum hose from ventilation control solenoid valve. Connect hand pump to fitting. Apply vacuum. Vacuum should leak. Apply battery voltage across ventilation control solenoid valve terminals. Vacuum should hold. If ventilation control solenoid valve performs as specified, go to next step. If ventilation control solenoid valve does not perform as specified, replace ventilation control solenoid valve.
  3. Turn ignition on. Check voltage between ground and ventilation control solenoid valve connector terminal No. 1. If battery voltage exists, go to next step. If battery voltage does not exist, check wiring harness between ventilation control solenoid valve and control relay.
  4. Turn ignition off. Disconnect ECM connector B-108. Turn ignition on. Check voltage between ground and ECM connector B-108 terminal No. 31. If battery voltage exists, check ECM connector. If connector is okay, replace ECM. If battery voltage does not exist, check ventilation control solenoid valve connector and wiring harness between ventilation control solenoid valve and ECM.
  1. If engine temperature was less than 32°F (0°C) at startup, at least 8 minutes have passed since engine started. Engine coolant temperature is 113°F (45°C) or more. Intake air temperature is 41°F (5°C) or more. Atmospheric pressure is 11 psi (76 kPa). Volumetric efficiency is 30-55 percent. Code will set when sensor output voltage is 4.6 volts or more, or .1 volt or less, for 4 seconds.
  2. Same conditions as previous listed criteria, except volumetric efficiency is less than 30 percent. Code will set when sensor output voltage is more than 4.2 volts for 4 seconds.
  3. Same conditions as previous listed criteria, except volumetric efficiency is more than 70 percent. Code will set when sensor output voltage is less than 4.2 volts for 4 seconds.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. Disconnect MDP sensor connector. Install Test Harness (MD991348) between MDP sensor and harness connector. With engine at idle, check voltage between ground and test harness terminal No. 1. Reading should be 0.8-2.4 volts. When throttle is opened suddenly, voltage should momentarily increase to more than 0.8-2.4 volts. If voltage is as specified, go to next step. If voltage is not as specified, go to step 3 .
  2. With ECM connector connected, check voltage between ground and ECM connector B-110 terminal No. 62 on Diamante, or ECM connector terminal No. 53 on Mirage. Start engine an allow it idle. If voltage is 0.8-2.4 volts, check ECM connector. If connector is okay, replace ECM. If voltage is not as specified, check wiring harness between ECM and MDP sensor connector.
  3. Disconnect MDP sensor connector. Turn ignition on. Check voltage between ground and MDP sensor connector terminal No. 3. Voltage should be 4.8-5.2 volts. Check continuity between ground and MDP sensor connector terminal No. 2. Continuity should exist. If voltage is not as specified or continuity does not exist, check ECM connector and wiring harness between MDP sensor connector and ECM. If connector and wiring are okay, replace ECM. If voltage is as specified and continuity exists, check MDP sensor connector and wiring harness between ECM and MDP sensor connector. If connector and wiring are okay, replace MDP sensor.
  1. Engine is running. Code will set when input voltage from generator FR terminal has been equal to battery voltage for 20 seconds.

Note. For terminal identification, see TERMINAL IDENTIFICATION in SELF-DIAGNOSTICS - INTRODUCTION article. For circuit and wire color identification, see WIRING DIAGRAMS article.

  1. With generator field connector connected. Check voltage between ground and field connector terminal No. 4. Ensure radiator fan is off. In sequence, turn headlights, rear defogger and stoplights on and then off. Voltage should drop 0.2-3.5 volts with accessory on. If voltage is not as specified, go to next step. If voltage is as specified, replace ECM.
  2. Disconnect generator field connector. Turn ignition on. Check voltage between ground and field connector terminal No. 4. If battery voltage exists, check field connector and wiring harness between ECM and field connector. If connector and wiring are okay, replace generator. If battery voltage does not exist, check ECM connector, junction connector and wiring harness between ECM and field connector. If wiring and connectors are okay, replace ECM.
  1. At least 2 seconds have passed since starting. Code will set when there is an abnormality in communication line with Transaxle Control Module (TCM), or there is a TCM malfunction.

Check connectors and wiring harness between ECM and TCM. Repair as necessary. If okay, check automatic transaxle control system. See appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS. If automatic transaxle control system is okay, replace ECM.

  1. Automatic transaxle control relay fail signal is input to ECM from Transaxle Control Module (TCM).

DTC P1751 is related to Electronic Automatic Transaxle (EATX) diagnostics. For diagnostic procedure, see appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS.

  1. Throttle Position (TP) sensor fail signal is input to ECM from Transaxle Control Module (TCM).

DTC P1795 is related to Electronic Automatic Transaxle (EATX) diagnostics. For diagnostic procedure, see appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS.

More articles — Engine Controls - Self-Diagnostics