Contents Wiring diagrams Section: Testing & Diagnostics All sections

Fuel and Emissions Systems: Other Honda Pilot II

Testing & Diagnostics 54 illustrations ~5132 words

Intermittent Failures

The term intermittent failure means a system may have had a failure, but it checks OK now. If the malfunction indicator lamp (MIL) on the dash does not come on, check for poor connections or loose terminals at all connectors related to the circuit that you are troubleshooting. If the MIL was on but then went out, the original problem may have been intermittent.

Service Information

Periodically, new PCM software or new service procedures may become available. Always check online for the latest software or service information related to the DTCs or symptoms you are troubleshooting.

Opens and Shorts

Open and short are common electrical terms. An open is a break in a wire or at a connection. A short is an accidental connection of a wire to ground or to another wire. In simple electronics, this usually means something won't work at all. With complex electronics (such as PCMs) this can sometimes mean something works, but not the way it's supposed to.

Scheme 4

Scheme 4: If the MIL (Malfunction Indicator Lamp) Has Come On
  1. Start the engine, and check the MIL (A). NOTE: If the ignition switch is turned to ON (II), and the engine is not started, the MIL stays on for 15-20 seconds (see «HOW TO SET READINESS CODES»(ref-333557-S37864202052009072100000) ).
  2. If the MIL stays on, connect the HDS to the data link connector (DLC) (A) located under the driver's side of the dashboard.
  3. Turn the ignition switch to ON (II).
  4. Make sure the HDS communicates with the PCM and all other vehicle systems. If it doesn't, go to «DLC CIRCUIT TROUBLESHOOTING»(ref-333558-S02093989162009072100000) .
  5. Check the diagnostic trouble code (DTC) and note it. Also check the freeze data and/or on-board snapshot data, and download any data found. Then refer to the indicated DTC's troubleshooting, and begin the appropriate troubleshooting procedure. NOTE: Freeze data indicates the engine conditions when the first system malfunction, misfire, or fuel trim malfunction that activated the MIL was detected. The HDS can read the DTC, freeze data, on-board snapshot, current data, and other powertrain control module (PCM) data. For specific operations, refer to the user's manual that came with the HDS.
  6. If no DTCs are found, go to «MIL CIRCUIT TROUBLESHOOTING»(ref-333558-S10340315042009072100000) .

If the MIL Did Not Stay On

If the MIL did not stay on but there is a driveability problem, do the symptom troubleshooting.

HDS Clear Command

The PCM stores various specific data to correct the system even if there is no electrical power such as when the battery negative terminal or No. 19 MAIN (15 A) fuse are disconnected. Stored data based on failed parts should be cleared by using the CLEAR COMMAND of the HDS, if parts are replaced.

The HDS has three kinds of clear commands to meet this purpose. They are DTC clear, PCM reset, and CKP pattern clear. DTC clear command erases all stored DTC codes, freeze data, and on-board snapshot, and readiness codes. This must be done with the HDS after reproducing the DTC during troubleshooting.

The PCM reset command erases all stored DTC codes, freeze data, on-board snapshot, and all specific data to correct the system except CKP pattern. If the CKP pattern data in the PCM was cleared, you must do the CKP pattern learn procedure. The CKP pattern clear command erases only CKP pattern data. This command is for repair of a misfire or the CKP sensor.

Clear/Learn Procedure (With the HDS)

  1. Connect the HDS to the data link connector (DLC) (A) located under the driver's side of the dashboard.
  2. Turn the ignition switch to ON (II).
  3. Make sure the HDS communicates with the PCM and all other vehicle systems. If it doesn't, go to «DLC CIRCUIT TROUBLESHOOTING»(ref-333558-S02093989162009072100000) .
  4. Select CRANK PATTERN in the ADJUSTMENT MENU with the HDS.
  5. Select CRANK PATTERN LEARNING with the HDS, and follow the screen prompts.

Learn Procedure (without the HDS)

  1. Start the engine. Hold the engine speed at 3,000 RPM without load (in P or N) until the radiator fan comes on.
  2. Test-drive the vehicle on a level road: Decelerate (with the throttle fully closed) from an engine speed of 2,500 RPM down to 1,000 RPM with the transmission in 2.
  3. Repeat step 2 several times.
  4. Turn the ignition switch to LOCK (0).
  5. Turn the ignition switch to ON (II), and wait for 30 seconds. The CKP pattern learn procedure is complete.

OBD Status

The OBD status shows the current system status of each DTC and all of the parameters. This function is used to see if the repair was successfully completed. The results of diagnostic tests for the DTC are displayed as

  1. PASSED: The on board diagnosis is successfully finished.
  2. FAILED: The on board diagnosis has finished but failed.
  3. EXECUTING: The vehicle is in enable criteria conditions for the DTC and the on board diagnosis is running.
  4. NOT COMPLETED: The on board diagnosis was running but is out of the enable conditions of the DTC.
  5. OUT OF CONDITION: The vehicle has stayed out of the enable conditions for the DTC.

Electronic Control System

The functions of the fuel and emission control systems are managed by the powertrain control module (PCM).

Self-Diagnosis

The PCM detects a failure of a signal from a sensor or from another control unit and stores a pending DTC or a Confirmed DTC. Depending on the failure, a Confirmed DTC is stored in either the first or the second drive cycle. When a Confirmed DTC is stored, the PCM turns on the malfunction indicator lamp (MIL) by a signal sent to the gauge via F-CAN.

  1. One Drive Cycle Detection Method When an abnormality occurs in the signal from a sensor or from another control unit, the PCM stores a DTC and turns on the MIL immediately.
  2. Two Drive Cycle Detection Method

When an abnormality occurs in the signal from a sensor or from another control unit in the first drive cycle, the PCM stores a Pending DTC. The MIL does not come on at this time. If the failure continues in the second drive cycle, the PCM stores a DTC and turns on the MIL.

Fail-Safe Function

When an abnormality occurs in the signal from a sensor or from another control unit, the PCM ignores that signal and substitute a pre-programmed value, that allows the engine to continue running. This causes a Confirmed DTC to be stored and the MIL to come on.

MIL Bulb Check and Readiness Code Condition

When the ignition switch is turned to ON (II), the PCM turns on the MIL via the F-CAN circuit for about 15 to 20 seconds to check the bulb condition. If any readiness codes are not set to complete, the MIL flashes five times. If all readiness codes are set to complete, the MIL goes off.

Self Shut Down (SSD) Mode

After the ignition switch is turned to LOCK (0), the PCM stays on (up to 30 minutes). If the PCM connector is disconnected during this time, the PCM may be damaged. To cancel this mode, disconnect the negative cable from the battery or jump the SCS line with the HDS after the ignition switch is turned to LOCK (0).

Scheme 5

Scheme 5: PCM Inputs and Outputs at Connector A ([]) (49P)
Terminal numberWire colorTerminal nameDescriptionSignal
1WHTVBSOL2 (POWER SOURCE FOR SOLENOID VALVES)Power source for solenoid valveWith ignition switch ON (II): battery voltage
2PNKSLS (SHIFT LOCK SOLENOID)Drives shift lock solenoidWith ignition switch ON (II), in P, brake pedal pressed, and accelerator released: about 0 V
3LT GRNSTRLY (STARTER RELAY)Drives starter cut relayWith ignition switch ON (II): about 0 V
4WHTFANL (RADIATOR FAN CONTROL)Drives A/C condenser fan relayWith condenser fan running: about 0 V With condenser fan stopped: battery voltage
5PURFANH (RADIATOR FAN CONTROL)Drives radiator fan relayWith radiator fan running: about 0 V With radiator fan stopped: battery voltage
6GRNMRLY (PGM-FI MAIN RELAY 1)Drives PGM-FI main relay 1With ignition switch ON (II): about 0 V With ignition switch to LOCK (0): battery voltage
7BRNBKSWNC (BRAKE PEDAL POSITION SWITCH)Detects brake pedal position switch signalWith ignition switch ON (II) and brake pedal released: battery voltage With ignition switch ON (II) and brake pedal pressed: about 0 V
8LT BLUBKSW (BRAKE PEDAL POSITION SWITCH)Detect brake pedal position switch signalWith brake pedal released: about 0 V With brake pedal pressed: battery voltage
9YELVG- (MASS AIR FLOW (MAF) SENSOR-SIDE)Ground for MAF sensor signal
10ORNELD (ELECTRICAL LOAD DETECTOR (ELD))Detects ELD signalWith ignition switch ON (II): about 0.1-4.8 V (depending on electrical load)
11GRNIMOFPR (IMMOBILIZER FUEL PUMP RELAY)Drives PGM-FI main relay 2 (FUEL PUMP)About 0 V for 2 seconds after turning ignition switch ON (II), then battery voltage
13YELACC (A/C CLUTCH RELAY)Drives A/C clutch relayWith compressor ON: about 0 V With compressor OFF: battery voltage
14PURCSSAMA (CYLINDER STOP SOLENOID A SIGNAL)Outputs rocker arm oil control solenoid B (Bank 1) drive signalRocker arm oil control solenoid B (Bank 1) ON: battery voltage Rocker arm oil control solenoid B (Bank 1) OFF: about 0 V
15LT BLUCSSAMC (CYLINDER STOP SOLENOID C SIGNAL)Outputs rocker arm oil control solenoid A (Bank 2) drive signalRocker arm oil control solenoid A (Bank 2) ON: battery voltage Rocker arm oil control solenoid A (Bank 2) OFF: about 0 V
16PNKATPP (TRANSMISSION RANGE SWITCH P POSITION)Detects transmission range switch P position signalIn P: about 0 V In any position other than P: battery voltage
17BLUD3SW (D3 SWITCH)Detects D3 switch signalD3 switch released: battery voltage D3 switch pressed: about 0 V
18PURAPSA (ACCELERATOR PEDAL POSITION (APP) SENSOR A)Detects APP sensor A signalWith ignition switch ON (II) and accelerator pedal pressed: about 4.7 V With ignition switch ON (II) and accelerator pedal released: about 1.0 V
19GRYAPSB (ACCELERATOR PEDAL POSITION (APP) SENSOR B)Detects APP sensor B signalWith ignition switch ON (II) and accelerator pedal pressed: about 2.3 V With ignition switch ON (II) and accelerator pedal released: about 0.5 V
20LT BLUVG+ (MASS AIR FLOW (MAF) SENSOR + SIDE)Detects MAF sensor signalAt idle: 1.1-1.6 V (between VG+ terminal and VG-terminal)
21PURECT2 (ENGINE COOLANT TEMPERATURE (ECT) SENSOR 2)Detects ECT sensor 2 signalWith ignition switch ON (II): about 0.1-4.8 V (depending on engine coolant temperature)
22LT GRNVSV (EVAPORATIVE EMISSION (EVAP) CANISTER VENT SHUT VALVE)Drives EVAP canister vent shut valveWith ignition switch ON (II): battery voltage
24REDVCC3 (SENSOR VOLTAGE)Provides sensor reference voltageWith ignition switch ON (II): about 5.0 V
25ORNVCC4 (SENSOR VOLTAGE)Provides sensor reference voltageWith ignition switch ON (II): about 5.0 V
26WHTSG3 (SENSOR GROUND)Sensor groundLess than 0.2 V at all times
27BRNSG4 (SENSOR GROUND)Sensor groundLess than 0.2 V at all times
28GRNSTRLDDetects starter cut relay 2With ignition switch in START (III): battery voltage
29REDETCSRLY (ELECTRONIC THROTTLE CONTROL SYSTEM (ETCS) CONTROL RELAY)Drives electronic throttle control system (ETCS) control relayWith ignition switch ON (II): about 0 V
30BLUVSSOUT (VEHICLE SPEED SIGNAL OUTPUT)Sends vehicle speed sensor signalDepending on vehicle speed: pulses
31LT BLUSTS (STARTER SWITCH SIGNAL)Detects starter switch signalWith ignition switch in START (III) position: battery voltage With ignition switch in any other position: about 0 V
32BRNSCS (SERVICE CHECK SIGNAL)Detects service check signalWith the service check signal shorted with the HDS: about 0 V With the service check signal opened: about 5.0 V
33YELNEP (ENGINE SPEED PULSE)Outputs engine speed pulseWith engine running: pulses
34GRNCKPOUT (CRANKSHAFT POSITION (CKP) OUTPUT SIGNAL)Sends CKP signal to engine mount control unitWith engine running: pulses
35REDCMPOUT (CAMSHAFT POSITION (CMP) OUTPUT SIGNAL)Sends CMP signal to engine mount control unitWith engine running: pulses
36LT BLUVCC7 (SENSOR VOLTAGE)Provides sensor reference voltageWith ignition switch ON (II): about 5.0 V
37BLKSG7 (SENSOR GROUND)Sensor groundLess than 1.0 V at all times
38BLUPSPSW (POWER STEERING PRESSURE SWITCH SIGNAL)Detects PSP switch signalAt idle with steering wheel in straight ahead position: about 0 V At idle with steering wheel at full lock: battery voltage
39LT GRNFTP (FUEL TANK PRESSURE (FTP) SENSOR)Detects FTP sensor signalWith ignition switch ON (II) and fuel fill cap removed: about 2.5 V
40PNKSUBRLY (PGM-FI SUBRELAY)Drives PGM-FI subrelayWith ignition switch ON (II): about 0 V
41BRNLG3 (LOGIC GROUND)Ground circuit for PCMLess than 1.0 V at all times
44 *1GRYWEN (WRITE ENABLE SIGNAL)Detects write enable signalWith ignition switch ON: about 0 V
46LT BLUS-NET5V (SERIAL COMMUNICATION FOR IMMOBILIZER)Sends serial communication signalWith ignition switch ON (II): pulses With key removed from ignition switch: about 5.0 V
48WHTCANH (CAN COMMUNICATION SIGNAL HIGH)Sends communication signalWith ignition switch ON (II): pulses
49REDCANL (CAN COMMUNICATION SIGNAL LOW)Sends communication signalWith ignition switch ON (II): pulses

TERMINAL DESCRIPTION TABLE

Scheme 6

Scheme 6: PCM Inputs and Outputs at Connector B (delta) (49P)
Terminal numberWire colorTerminal nameDescriptionSignal
1BLKPG2 (POWER GROUND)Ground circuit for PCMLess than 1.0 V at all times
2BLK/YELVBSOL1 (POWER SOURCE FOR SOLENOID VALVES)Power source for solenoid valvesWith ignition switch ON (II): battery voltage
3YEL/BLKIGP (POWER SOURCE)Power source for PCM circuitWith ignition switch ON (II): battery voltage
4BRNINJ1 (No. 1 INJECTOR)Drives No. 1 injectorAt idle: duty controlled With ignition switch ON (II): battery voltage
5BLK/REDINJ5 (No. 5 INJECTOR)Drives No. 5 injector
6YELINJ4 (No. 4 INJECTOR)Drives No. 4 injector
7BLUINJ3 (No. 3 INJECTOR)Drives No. 3 injector
8REDINJ2 (No. 2 INJECTOR)Drives No. 2 injector
9WHT/BLUINJ6 (No. 6 INJECTOR)Drives No. 6 injector
10BRN/WHTLSB (A/T CLUTCH PRESSURE CONTROL SOLENOID VALVE B)Drives A/T clutch pressure control solenoid valve BWith ignition switch ON (II): current controlled
11BLK/REDIGPLS5 (No. 5 IGNITION COIL PULSE)Drives No. 5 ignition coilWith ignition switch ON (II): about 0 V With engine running: pulses
12BRN/WHTIGPLS6 (No. 6 IGNITION COIL PULSE)Drives No. 6 ignition coil
13BLUVSB1 (VS CELL+ BANK 1)Detects rear A/F sensor (Bank 1, sensor 1) VS CELL signalWith engine running: about 3.4-4.8 V
14RED/BLUVSB2 (VS CELL+ BANK 2)Detects front A/F sensor (Bank 2, sensor 1) VS CELL signalWith fully warmed up engine running: about 3.4-4.8 V
15REDVCENTB1 (VIRTUAL GROUND BANK 1)Reference voltage supply for rear A/F sensor (Bank 1, sensor 1)With fully warmed up engine at idle: about 3.4-4.8 V
16WHTSHO2SB2 (FRONT SECONDARY HEATED OXYGEN SENSOR (FRONT SECONDARY HO2S) BANK 2, SENSOR 2)Detects front secondary HO2S (Bank 2, sensor 2) signalWith throttle fully opened from idle and fully warmed up engine: about 0.6 V With throttle quickly closed: below 0.4 V
17RED/BLKTPSA (THROTTLE POSITION (TP) SENSOR A)Detects TP sensor A signalWith throttle fully open: about 3.9 V With throttle fully closed: about 0.9 V
18BLUVCC5 (SENSOR VOLTAGE)Provides sensor reference voltageWith ignition switch ON (II): about 5.0 V
19WHT/BLKIMTM (INTAKE MANIFOLD TUNING (IMT) VALVE MONITOR)Detects IMT valve positionWith ignition switch ON (II): about 5.0 V With engine speed above 4,300 RPM: about 0 V
20BLU/WHTVCMSWC (ROCKER ARM OIL PRESSURE SWITCH C)Detects front rocker arm oil pressure switch signalWith ignition switch ON (II) or at idle: battery voltage
21GRN/REDLSC (A/T CLUTCH PRESSURE CONTROL SOLENOID VALVE C)Drives A/T clutch pressure control solenoid valve CWith ignition switch ON (II): current controlled
22WHT/BLUIGPLS3 (No. 3 IGNITION COIL PULSE)Drives No. 3 ignition coilWith ignition switch ON (II): about 0 V With engine running: pulses
23BRNIGPLS4 (No. 4 IGNITION COIL PULSE)Drives No. 4 ignition coil
24RED/WHTVCENTB2 (VIRTUAL GROUND BANK 2)Reference voltage supply for front A/F sensor (Bank 2, sensor 1)With fully warmed up engine at idle: about 3.4-4.8 V
25GRNSHO2SB1 (REAR SECONDARY HEATED OXYGEN SENSOR (REAR SECONDARY HO2S) BANK1, SENSOR 2)Detects rear secondary HO2S (Bank 1, sensor 2) signalWith throttle fully opened from idle and fully warmed up engine: about 0.6 V With throttle quickly closed: below 0.4 V
26RED/BLUTPSB (THROTTLE POSITION (TP) SENSOR B)Detects TP sensor B signalWith throttle fully open: about 4.1 V With throttle fully closed: about 1.7 V
28GRN/WHTCSSC (CYLINDER STOP SOLENOID C)Drives rocker arm oil control solenoid A (Bank 2)With ignition switch ON (II) or at idle: about 0 V
29YEL/GRNIGPLS1 (No. 1 IGNITION COIL PULSE)Drives No. 1 ignition coilWith ignition switch ON (II): about 0 V With engine running: pulses
30BLU/REDIGPLS2 (No. 2 IGNITION COIL PULSE)Drives No. 2 ignition coil
31GRNIPB1 (IP CELL+BANK 1)Detects rear A/F sensor (Bank 1, sensor 1) pump cellWith engine running: about 2.0-5.6 V
32GRN/REDIPB2 (IP CELL+BANK 2)Detects front A/F sensor (Bank 2, sensor 1) pump cellWith engine running: about 2.0-5.6 V
33GRNSG5 (SENSOR GROUND)Sensor groundLess than 0.2 V at all times
34GRN/WHTSG1 (SENSOR GROUND)Sensor groundLess than 0.2V at all times
35GRN/REDMAP (MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR)Detects MAP sensor signalWith ignition switch ON (II): about 3.0 V At idle: about 1.0 V (depending on engine speed)
36YEL/REDVCC1 (SENSOR VOLTAGE)Provides sensor reference voltageWith ignition switch ON (II): about 5.0 V
37REDNM (INPUT SHAFT (MAINSHAFT) SPEED SENSOR)Detects input shaft (mainshaft) speed sensor signalsWith ignition switch ON (II): about 0 V or about 5.0 V With engine idling in N: about 2.5 V
38BLUNC (OUTPUT SHAFT (COUNTERSHAFT) SPEED SENSOR)Detects output shaft (countershaft) speed sensor signalWith ignition switch ON (II) and front wheels turned by hand: pulses
39GRN/YELCSSA (CYLINDER STOP SOLENOID A)Drives rocker arm oil control solenoid B (Bank 1)With ignition switch ON (II) or at idle: about 0 V
40BLKPG1 (POWER GROUND)Ground circuit for PCMLess than 0.2 V at all times
41BRN/YELLG2 (LOGIC GROUND)Ground circuit for PCMLess than 0.2 V at all times
42BLK/YELIG1 (IGNITION SIGNAL)Detects ignition signalWith ignition switch ON (II): battery voltage
45BLUCKP (CRANKSHAFT POSITION (CKP) SENSOR)Detects CKP sensor signalWith engine running: pulses
46GRNCMP (CAMSHAFT POSITION (CMP) SENSOR)Detects CMP sensor signalWith engine running: pulses
49GRN/REDCSSB (CYLINDER STOP SOLENOID B)Drives rocker arm oil control solenoid A (Bank 1)With ignition switch ON (II) or at idle: about 0 V

TERMINAL DESCRIPTION TABLE

Scheme 7

Scheme 7: PCM Inputs and Outputs at Connector C (o) (49P)
Terminal numberWire colorTerminal nameDescriptionSignal
1BLKPGMETCS (POWER GROUND ETCS)Ground circuit for PCMLess than 0.2 V at all times
2BLUETCSM+ (THROTTLE ACTUATOR +SIDE)Drives throttle actuatorWith ignition switch ON (II): about 0 V
3GRNETCSM- (THROTTLE ACTUATOR-SIDE)Ground for throttle actuatorWith ignition switch ON (II): about 0 V
4YEL/GRNIG1 ETCS (IGNITION SIGNAL ETCS)Detects ignition signalWith ignition switch ON (II): battery voltage
5BLK/WHTSO2SHTCB1 (REAR SECONDARY HEATED OXYGEN SENSOR (REAR SECONDARY HO2S) (BANK 1, SENSOR 2) HEATER CONTROLDrives rear secondary HO2S heater (Bank 1, sensor 2)With ignition switch ON (II): battery voltage With fully warmed up engine running: duty controlled
6BLK/WHTAFSHTCB1 (REAR AIR FUEL RATIO (REAR A/F) SENSOR HEATER CONTROL BANK 1, SENSOR 1)Drives rear A/F sensor heater (Bank 1, sensor 1)With ignition switch ON (II): battery voltage With fully warmed up engine running: about 0 V or duty controlled
7GRN/REDSO2SHTCB2 (FRONT SECONDARY HEATED OXYGEN SENSOR (SECONDARY HO2S) HEATER)Drives front secondary HO2S heater (Bank 2, sensor 2)With ignition switch ON (II): battery voltage With fully warmed up engine running: duty controlled
8GRN/WHTAFSHTCB2 (FRONT AIR FUEL RATIO (FRONT A/F) SENSOR HEATER CONTROL BANK 2, SENSOR 1)Drives front A/F sensor heater (Bank 2, sensor 1)With ignition switch ON (II): battery voltage With fully warmed up engine running: about 0 V or duty controlled
9GRN/REDSHD (SHIFT SOLENOID VALVE D)Drives shift solenoid valve DWith engine running in N, and in D and 2 during no lock-up condition: about 0 V With engine running in P and R, and in D during lock-up condition: battery voltage
10BLU/REDEGR (EXHAUST GAS RECIRCULATION (EGR) VALVE)Drives EGR valveWith EGR operating: duty controlled With EGR not operating: about 0 V
11YEL/BLUVCC6 (SENSOR VOLTAGE)Provides sensor reference voltageWith ignition switch ON (II): about 5.0 V
12YEL/BLUVCC2 (SENSOR VOLTAGE)Provides sensor reference voltageWith ignition switch ON (II): about 5.0 V
15GRN/REDSG6 (SENSOR GROUND)Sensor groundLess than 0.2 V at all times
16GRN/YELSG2 (SENSOR GROUND)Sensor groundLess than 1.0 V at all times
17YEL/GRNATPD (TRANSMISSION RANGE SWITCH D)Detects transmission range switch D position signal inputIn D: about 0 V In any position other than D: battery voltage
18BLU/YELATPFWD (TRANSMISSION RANGE SWITCH FWD)Detects transmission range switch FWD position signalIn D, 2 and 1: about 0 V In any position other than D, 2 and 1: battery voltage
19RED/WHTATPRVS (TRANSMISSION RANGE SWITCH RVS)Detects transmission range switch RVS position signal inputIn P, R and N: about 0 V In any position other than P, R and N: battery voltage
20BLU/YELSHA (SHIFT SOLENOID VALVE A)Drives shift solenoid valve AWith engine running in R, D (in 2nd and 3rd gears) and second: battery voltage With engine running in P, N, D (in 1st, 4th and 5th gears), and 1: about 0 V
21REDLSA (ATT CLUTCH PRESSURE CONTROL SOLENOID VALVE A)Drives A/T clutch pressure control solenoid valve AWith ignition switch ON (II): current controlled
22BLU/YELPOIL (ENGINE OIL PRESSURE SENSOR)Detects rocker arm oil pressure sensor signalWith ignition switch ON (II): about 0.8 V (depending on engine oil pressure)
24RED/YELIAT (INTAKE AIR TEMPERATURE (IAT) SENSOR)Detects IAT sensor signalWith ignition switch ON (II): about 0.1-4.8 V (depending on intake air temperature)
25WHTATPR (TRANSMISSION RANGE SWITCH R)Detects transmission range switch R position signal inputIn R: about 0 V In any position other than R: battery voltage
26RED/BLKATPN (TRANSMISSION RANGE SWITCH N)Detects transmission range switch N position signal inputIn N: about 0 V In any position other than N: battery voltage
27BLU/BLKOP2SW (2ND CLUTCH TRANSMISSION FLUID PRESSURE SWITCH)Detects transmission fluid pressure switch A (2nd clutch) signalWith ignition switch ON (II): Without 2nd clutch pressure: about 5.0 V With 2nd clutch pressure: about 0 V
28GRN/WHTSHB (SHIFT SOLENOID VALVE B)Drives shift solenoid valve BWith engine running in P, R, N, 2, D (in 1st, 2nd and 5th gears): battery voltage With engine running in D (in 3rd and 4th gears): about 0 V
30BLU/YELVCMSWB (ROCKER ARM OIL PRESSURE SWITCH B)Detects rear rocker arm oil pressure switch signalWith ignition switch ON (II) or at idle: battery voltage
32RED/WHTECT1 (ENGINE COOLANT TEMPERATURE SENSOR (ECT) SENSOR 1)Detects ECT sensor 1 signalWith ignition switch ON (II): about 0.1-4.8 V (depending on engine coolant temperature)
33BLU/YELATFT (TATF TEMPERATURE SENSOR)Detects ATF temperature signalWith ignition switch ON (II): about 0.2-4.0 V (about 1.8 V at operating temperature, depending on ATF temperature)
34WHT/BLKEGRP (EXHAUST GAS RECIRCULATION (EGR) VALVE POSITION SENSOR)Detects EGR valve position sensor signalWith engine running: about 1.2-3.0 V (depending on EGR valve lift)
35BRNATP1 (TRANSMISSION RANGE SWITCH 1)Detects transmission switch 1 signalIn 1: about 0 V In any position other than 1: battery voltage
37BLU/YELOP4SW (4TH CLUTCH TRANSMISSION FLUID PRESSURE SWITCH)Detects 4th clutch transmission fluid pressure switch signalWith ignition switch ON (II): Without 4th clutch pressure: about 5.0 V With 4th clutch pressure: about 0 V
38BLU/WHTOP3SW (3RD CLUTCH TRANSMISSION FLUID PRESSURE SWITCH)Detects transmission fluid pressure switch B (3rd clutch) signalWith ignition switch ON (II): Without 3rd clutch pressure: about 5.0 V With 3rd clutch pressure: about 0 V
39GRNSHC (SHIFT SOLENOID VALVE C)Drives shift solenoid valve CWith engine running in D (in 1st, 3rd and 5th gears), and 1: battery voltage With engine running in P, R, N, D (in 2nd and 4th gears), and D3 (in 2nd gear), and 2: about 0 V
40RED/YELPCS (EVAPORATIVE EMISSION (EVAP) CANISTER PURGE VALVE)Drives EVAP canister purge valveWith engine running, engine coolant below 140°F (60°C): battery voltage With engine running, engine coolant above 140°F (60°C): duty controlled
41BRN/YELLG1 (LOGIC GROUND)Ground circuit for PCMLess than 0.2 V at all times
42WHT/BLUALTL (ALTERNATOR L SIGNAL)Detects alternator L signalWith ignition switch ON (II): about 0 V With engine running: battery voltage
43WHT/GRNALTC (ALTERNATOR CONTROL)Sends alternator control signalWith fully warmed up engine running: about 7.5 V (depending on electrical load)
44WHT/REDALTF (ALTERNATOR FR SIGNAL)Detects alternator FR signalWith engine running: about 0-5.0 V (depending on electrical load)
46BLUATP2 (TRANSMISSION RANGE SWITCH 2)Detects transmission switch 2 signal inputIn 2: about 0 V In any position other than 2: battery voltage
47RED/BLUKS (KNOCK SENSOR)Detects knock sensor signalWith engine knocking: pulses
48WHT/BLUIMT+ (INTAKE MANIFOLD TUNING (IMT) ACTUATOR + SIDE)Drives IMT actuatorWith ignition switch ON (II): battery voltage
49WHT/REDIMT- (INTAKE MANIFOLD TUNING (IMT) ACTUATOR - SIDE)Drives IMT actuatorWith ignition switch ON (II): battery voltage

TERMINAL DESCRIPTION TABLE

Scheme 8

Scheme 8: PCM Electrical Connections

Scheme 9

Scheme 9

Scheme 10

Scheme 10

Scheme 11

Scheme 11

Scheme 12

Scheme 12

Scheme 13

Scheme 13

Scheme 14

Scheme 14

Scheme 15

Scheme 15: PCM Circuit Diagram

Scheme 16

Scheme 16

Scheme 17

Scheme 17

Scheme 18

Scheme 18

Scheme 19

Scheme 19

Scheme 20

Scheme 20

Scheme 21

Scheme 21

Scheme 22

Scheme 22

Scheme 23

Scheme 23

Scheme 24

Scheme 24

Scheme 25

Scheme 25

Scheme 26

Scheme 26

Scheme 27

Scheme 27

Scheme 28

Scheme 28

Scheme 29

Scheme 29

Scheme 30

Scheme 30

PGM-FI System

The programmed fuel injection (PGM-FI) system is a sequential multiport fuel injection system.

Alternator Control

The alternator signals the PCM during charging. The PCM then controls the voltage generated at the alternator according to the electrical load determined by the electrical load detector (ELD) and the driving mode. This reduces engine load to improve fuel economy.

Air Conditioning (A/C) Compressor Clutch Relay

When the PCM receives a demand for cooling from the A/C system, it delays the compressor from being energized, and enriches the mixture to assure smooth transition to the A/C mode.

Air Fuel Ratio (A/F) Sensor

The A/F sensor operates over a wide air/fuel range. The A/F sensor is installed upstream of the warm up three way catalytic converter (WU-TWC), and sends signals to the PCM which varies the duration of fuel injection accordingly.

Scheme 31

Scheme 31: Air Fuel Ratio (A/F) Sensor

Barometric Pressure (BARO) Sensor

The BARO sensor is inside the PCM. It converts atmospheric pressure into a voltage signal that is used by the PCM to modify the basic duration of the fuel injection discharge.

Camshaft Position (CMP) Sensor

The CMP sensor detects the position of the No. 1 cylinder as a reference for sequential fuel injection to each cyclinder.

Scheme 32

Scheme 32: Camshaft Position (CMP) Sensor

Crankshaft Position (CKP) Sensor

The CKP sensor detects crankshaft speed and is used by the PCM to determine ignition timing, timing for the fuel injection of each cylinder, and engine misfire detection.

Scheme 33

Scheme 33: Crankshaft Position (CKP) Sensor

Engine Coolant Temperature (ECT) Sensor 1 and 2

ECT sensors 1 and 2 are temperature dependent resistors (thermistors). The resistance decreases as the engine coolant temperature increases.

Scheme 34

Scheme 34: Engine Coolant Temperature (ECT) Sensor 1 and 2

Ignition Timing Control

The PCM contains the memory for basic ignition timing at various engine speeds and manifold absolute pressures. It also adjusts the timing according to engine coolant temperature.

Injector Timing and Duration

The PCM contains the memory for basic discharge duration at various engine speeds and manifold pressures. The basic discharge duration, after being read out from the memory, is further modified by inputs sent from various sensors to obtain the final discharge duration.

By monitoring long term fuel trim, the PCM can detect long term malfunctions in the fuel system and set (DTCs) if needed.

Knock Sensor

The knock control system adjusts the ignition timing to minimize knock.

Scheme 35

Scheme 35: Knock Sensor

Malfunction Indicator Lamp (MIL) Indication (In Relation to Readiness Codes)

The vehicle has certain readiness codes that are part of the on-board diagnostics for the emissions systems. If the vehicle's battery has been disconnected or gone dead, if DTCs have been cleared, or if the PCM has been reset, these codes are reset. In some states, part of the emissions testing is to make sure these codes are set to complete. If all of them are not set to complete, the vehicle may fail the test, or the test cannot be finished.

To check if the readiness codes are set to complete, turn the ignition switch to ON (II), but do not start the engine. The MIL will come on for 15-20 seconds. If it then goes off, the readiness codes are complete. If it flashes five times, one or more readiness codes are not set to complete. To set each code, drive the vehicle or run the engine as described in the procedures (see HOW TO SET READINESS CODES ).

Manifold Absolute Pressure (MAP) Sensor

The MAP sensor converts manifold absolute pressure into electrical signals to the PCM.

Scheme 36

Scheme 36: Manifold Absolute Pressure (MAP) Sensor

Mass Air Flow (MAF) Sensor/Intake Air Temperature (IAT) Sensor

The mass airflow (MAF) sensor/intake air temperature (IAT) sensor contains a hot wire, a cold film, and a thermistor. The sensor is in the intake passage. The resistance of the hot wire and thermistor change due to intake air temperature and airflow. The control circuit in the MAF sensor controls the current to keep the hot wire at a set temperature. The current is converted to voltage in the control circuit, then output to the PCM.

Identifying Manifold Absolute Pressure (MAP) Sensor Terminal & O-Ring. Scheme 37

Scheme 37: Identifying Manifold Absolute Pressure (MAP) Sensor Terminal & O-Ring

Output Shaft (Countershaft) Speed Sensor

This sensor detects countershaft speed.

Scheme 38

Scheme 38: Output Shaft (Countershaft) Speed Sensor

Secondary Heated Oxygen Sensor (Secondary HO2S)

The secondary HO2S detects the oxygen content in the exhaust gas downstream of the warm up three way catalytic converter (WU-TWC), and sends signals to the PCM. To stabilize its output, the sensor has an internal heater. The PCM compares the HO2S output with the A/F sensor output to determine catalyst efficiency. The secondary HO2S is installed in each bank, downstream of the WU-TWC.

Scheme 39

Scheme 39: Secondary Heated Oxygen Sensor (Secondary HO2S)

Starter Control System Diagram

The starter control system controls the starter motor.

  1. When the ignition switch is turned to start (III), the PCM applies current to starter cut relay 1 (STR) and starter cut relay 2, then battery voltage is applied to the starter motor to run it.
  2. Once the ignition switch is released, the PCM keeps the starter motor running until the engine starts. If the PCM detects that the engine starts, the PCM stops applying current to the relays, then the starter motor stops.
  3. If you turn the ignition switch to START (III) position while the engine is running, the starter motor does not operate.
  4. In the following cases, PCM stops the starter motor; After the starter motor operates for 10 seconds (to prevent the starter motor from overheating). If the engine RPM is to high during starter motor operation.
  5. If there is a problem with the starter control system, a message appears on the gauge display. When the warning message is turned on, the vehicle can only be started by turning and holding the ignition switch in the start position until the engine.

Scheme 40

Scheme 40

Electronic Throttle Control System

The throttle is electronically controlled by the electronic throttle control system. Refer to the system diagram to see a functional layout of the system.

Idle control: When the engine is idling, the PCM controls the throttle actuator to maintain the proper idle speed according to engine loads.

Acceleration control: When the accelerator pedal is pressed, the PCM opens the throttle valve depending on the accelerator pedal position (APP) sensor signal.

Cruise control: The PCM controls the throttle actuator to maintain the set speed when cruise control is operating. The throttle actuator takes the place of the cruise control actuator.

Accelerator Pedal Position (APP) Sensor

As the accelerator pedal position changes, the sensor varies the signal voltage to the PCM which then controls the throttle.

Scheme 41

Scheme 41: Accelerator Pedal Position (APP) Sensor

Throttle Body

The throttle body is a single-barrel side draft type. The lower portion of the throttle valve is heated by engine coolant from the cylinder head to prevent icing of the throttle plate.

Scheme 42

Scheme 42: Throttle Body

Electronic Throttle Control System Diagram

The electronic throttle control system consists of the throttle actuator, throttle position (TP) sensor A/B, accelerator pedal position (APP) sensor A/B, the electronic throttle control system (ETCS) control relay, and the PCM.

Scheme 43

Scheme 43: Electronic Throttle Control System Diagram

Variable Cylinder Management (VCM) System

The VCM system activates the cylinders based on the driving condition. The system has three modes: 6 cylinder mode (all cylinder operation), 4 cylinder mode (pauses the No. 3 and No. 4 cylinders), and 3 cylinder (pauses the rear bank of cylinders). On paused cylinders, the intake and exhaust valves are kept closed. Since the valves are closed, the frictional losses from the valve spring compression and pumping are reduced because no air is compressed in the cylinder. This reduces engine drag.

Note. Cylinders No. 5 and No. 6 are not controlled by the VCM and operate in all modes.

During 6 Cylinder Mode

With rocker arm oil control solenoid A (Bank 1), B (Bank 1), and A (Bank 2) OFF, the rocker arm oil control valves direct oil pressure. Oil pressure enters the secondary rocker arm from the oil passage in the rocker shaft, and it moves the VTEC switching piston, sliding it into the primary rocker arm and locking primary rocker arms and secondary rocker arms together. The rocker arms are lifted by the camshaft, and all cylinders are active.

Scheme 44

Scheme 44: During 6 Cylinder Mode

During 4 Cylinder Mode

With rocker arm oil control solenoid B (Bank 1) and A (Bank 2) turned on by the PCM, the front and rear rocker arm oil control valves switch the oil pressure. Oil pressure then enters the No. 3 and No. 4 cylinder's primary rocker arm from the oil passage in the rocker shaft, causing the VTEC switching piston to slide into the secondary rocker arm and against the return spring. This disengages the primary rocker arm from the secondary rocker arm to stop valve activation. The No. 3 and No. 4 cylinder's rocker arms do not move, and the No. 3 and No. 4 cylinders are paused. In the other four cylinders, oil pressure from the rear rocker arm oil control valve locks the primary rocker arms and secondary rocker arms together. The rocker arms are moved by the camshaft, and the four cylinders are active.

Scheme 45

Scheme 45: During 4 Cylinder Mode

During 3 Cylinder Mode

When rocker arm oil control solenoid A (Bank 1) is turned on by the PCM, the rear rocker arm oil control valve switches the oil pressure. Oil pressure then enters the rear bank cylinder's primary rocker arms from the oil passage in the rocker shaft, causing the VTEC switching piston to slide into the secondary rocker arms and against the return spring. This disengages the primary rocker arms from the secondary rocker arms to stop valve activation. The rear bank cylinder's rocker arms do not move, and rear bank cylinders are paused. At the front bank, oil pressure from the front rocker arm oil control valve locks the No. 4 cylinder's primary and secondary rocker arms together. The No. 4 cylinder's rocker arms are moved by the camshaft, and all front bank cylinders are active.

Note. Bank 1 Solenoid B controls VCM function for cylinders No. 1, No. 2 and No. 3.

Scheme 46

Scheme 46: During 3 Cylinder Mode

Idle Control System

When the engine is cold, the A/C compressor is on, the transmission is in gear, the brake pedal is pressed, the power steering load is high, or the alternator is charging, the PCM controls current to the throttle actuator to maintain the correct idle speed.

Brake Pedal Position Switch

The brake pedal position switch signals the PCM when the brake pedal is pressed.

Power Steering Pressure (PSP) Switch

The PSP switch signals the PCM when the power steering load is high.

Fuel Cutoff Control

During deceleration with the throttle valve closed, current to the injectors is cut off to improve fuel economy at engine speeds over 850 RPM. Fuel cutoff control also occurs when the engine speed exceeds 6,400 RPM, regardless of the position of the throttle valve, to protect the engine from over-revving. When the vehicle is stopped, the PCM cuts the fuel at engine speeds over 5,000 RPM. On a cold engine, fuel cut occurs at a lower engine speed.

Fuel Pump Control

When the ignition switch is turned to ON (II), the PCM grounds PGM-FI main relay 2 (FUEL PUMP) which feeds current to the fuel pump for 2 seconds to pressurize the fuel system. With the engine starts, the PCM grounds PGM-FI main relay 2 (FUEL PUMP) and feeds current to the fuel pump. When the engine is not running and the ignition is on, the PCM cuts ground to PGM-FI main relay 2 (FUEL PUMP) which cuts current to the fuel pump.

PGM-FI Main Relay 1 and 2

PGM-FI main relay 1 is energized whenever the ignition switch is ON (II), to supply battery voltage to the PCM, power to the injectors, and power for PGM-FI main relay 2 (FUEL PUMP). PGM-FI main relay 2 (FUEL PUMP) is energized to supply power to the fuel pump for 2 seconds when the ignition switch is turned to ON (II), and when the engine is cranking or running.

Intake Manifold Tuning (IMT) Value

Engine power is adjusted by opening and closing the intake manifold tuning (IMT) valve. When the valve is closed, there is high torque at low engine speed. When the valve is open, there is high torque at high engine speed.

The intake manifold tuning (IMT) actuator contains a sensor that detects the IMT valve position and sends it to the PCM.

Scheme 47

Scheme 47: Intake Manifold Tuning (IMT) Value

Warm Up three Way Catalytic Converter (WU-TWC) and Under-floor Three Way Catalytic Converter (Under-floor TWC)

The WU-TWC/Under-floor TWC converts hydrocarbons (HC), carbon monoxide (CO), and oxides of nitrogen (NOx) in the exhaust gas to carbon dioxide (CO 2 ), nitrogen (N 2 ), and water vapor.

WU-TWC

Scheme 48

Scheme 48: Warm Up three Way Catalytic Converter (WU-TWC) and Under-floor Three Way Catalytic Converter (Under-

UNDER-FLOOR TWC

Scheme 49

Scheme 49

Exhaust Gas Recirculation (EGR) System

Refer to the system diagram to see a functional layout of the system.

EGR Valve

The EGR valve lowers peak combustion temperatures and reduces oxides of nitrogen emissions (NOx) by recirculating exhaust gas through the intake manifold and into the combustion chambers.

Exhaust Gas Recirculation (EGR) System Diagram

The EGR system reduces oxides of nitrogen (NOx) emissions by recirculating exhaust gas through the EGR pipe and the intake manifold, and into the combustion chambers. Routing the exhaust gas through the EGR pipe after the catalytic converter helps to prevent carbon deposits from forming in the intake manifold and the throttle body. The PCM memory includes the ideal EGR valve position for varying operating conditions.

The EGR valve position sensor detects the amount of EGR valve lift and sends it to the PCM. The PCM then compares it with the ideal lift in its memory (based on signals sent from other sensors). If there is any difference between the two, the PCM cuts current to the EGR valve.

Scheme 50

Scheme 50: Exhaust Gas Recirculation (EGR) System Diagram

Positive Crankcase Ventilation (PCV) System

The PCV valve prevents blow-by gasses from escaping into the atmosphere by venting them into the intake manifold.

Scheme 51

Scheme 51: Positive Crankcase Ventilation (PCV) System

Evaporative Emission (EVAP) Control System

Refer to the system diagram to see a functional layout of the system.

EVAP Canister

The EVAP canister temporarily stores fuel vapor from the fuel tank until it can be purged from the EVAP canister into the engine and burned.

EVAP Canister Purge Valve

When the engine coolant temperature is below 140°F (60°C) the PCM turns off the EVAP canister purge valve which cuts vacuum to the EVAP canister.

Scheme 52

Scheme 52: EVAP Canister Purge Valve

Fuel Tank Pressure (FTP) Sensor

The FTP sensor converts fuel tank absolute pressure into an electrical input to the PCM.

Scheme 53

Scheme 53: Fuel Tank Pressure (FTP) Sensor

EVAP Canister Vent Shut Valve

The EVAP canister vent shut valve is on the EVAP canister.

The EVAP canister vent shut valve controls the venting of the EVAP canister.

Scheme 54

Scheme 54: EVAP Canister Vent Shut Valve

Evaporative Emission (EVAP) Control Diagram

The EVAP controls minimize the amount of fuel vapor escaping into the atmosphere. Vapor from the fuel tank is temporarily stored in the EVAP canister until it can be purged from the EVAP canister into the engine and burned.

  1. The EVAP canister is purged by drawing fresh air through it and into a port on the intake manifold. The purging vacuum is controlled by the EVAP canister purge valve, which is opened by duty cycle control signal from the PCM whenever engine coolant temperature is above 140°F (60°C).
  2. During refueling, the fuel tank vapor control valve opens from pressure in the fuel tank, and feeds the fuel vapor to the EVAP canister, where its stored.

Fuel Cap Warning Message

The PCM will detect a loose or missing fuel fill cap as an evaporative system leak, and alerts the driver by showing a warning message in the gauge display.

The first time a leak is detected, a TIGHTEN FUEL CAP (multi-information display model) (CHECK FUEL CAP (odometer/outside temperature display model)) message appears in the gauge display (A). To scroll to another message, press the select/reset button. The TIGHTEN FUEL CAP/CHECK FUEL CAP message appears each time you restart the engine until the system turns the message off. Turn the engine off, then replace or tighten the fuel fill cap until clicks at least once.

Multi-information display model

Scheme 55

Scheme 55: Fuel Cap Warning Message

Odometer/outside temperature display model

Scheme 56

Scheme 56

Procedure

  1. Tighten the fuel fill cap until it clicks.
  2. Clear the Temporary DTC with the HDS.
  3. Verify there is no leak by doing the EVAP FUNCTION TEST in the INSPECTION MENU with the HDS.
  1. Tighten the fuel fill cap until it clicks.
  2. Start the engine, then turn the ignition switch to LOCK (0).
  3. Repeat step 2 more times.

The vehicle has certain readiness codes that are part of the on-board diagnostics for the emissions systems. If the vehicle's battery has been disconnected or gone dead, if the DTCs have been cleared, or if the PCM has been reset, these readiness codes are reset to incomplete. In some states, part of the emissions testing is to make sure these codes are set to complete. If all of them are not set to complete, the vehicle may fail the emission test, or the test cannot be finished.

To check if the readiness codes are set to complete, turn the ignition switch to ON (II), but do not start the engine. The MIL will come on for 15-20 seconds. If it then goes off, the readiness codes are set to complete. If it flashes five times, one or more readiness codes are not set to complete. To set readiness codes from incomplete to complete, do the procedure check for the appropriate code.

To check the status of a specific DTC system, check the OBD status in the DTC MENU with the HDS (see SUBSTITUTING THE PCM ). This screen displays the code, the current data list of the enable criteria, and the status of the readiness testing.

Catalytic Converter Monitor and Readiness Code

Note. During the procedure, do not turn the ignition switch to ACC (I) or LOCK (0). All readiness codes are cleared when the battery is disconnected, if the DTCs have been cleared, or if the PCM is reset with the HDS. Low ambient temperatures or excessive stop-and-go traffic may increase the drive time needed to switch the readiness code from incomplete to complete. The readiness code will not switch to complete until all the enable criteria are met. If a fault in the secondary HO2S system caused the MIL to come on, the readiness code cannot be set to complete until you correct the fault.

Enable Criteria

  1. ECT SENSOR 1 at 158°F (70°C) or more.
  2. IAT SENSOR at 20°F (-7°C) or more.
  3. Vehicle speed above 25 mph (40 km/h).
  1. Connect the HDS to the vehicle's data link connector (DLC), and bring up the READINESS CODEs screen for Catalyst in the DTCs MENU.
  2. Start the engine.
  3. Test-drive the vehicle under stop-and-go conditions with short periods of steady cruise. After about 5 miles (8 km), the readiness code should switch to complete.
  4. If the readiness code is still not set to complete, check for a Pending DTC with the HDS. If there is no DTC, one or more of the enable criteria were probably not met; repeat the procedure.

Evaporative Emission (EVAP) Control System Monitor and Readiness Code

Note. All readiness codes are cleared when the battery is disconnected, if the DTCs have been cleared, or if the PCM is reset with the HDS.

  1. Battery voltage is more than 10.5 V.
  2. Engine at idle.
  3. ECT SENSOR 1 and SENSOR 2 between 176°F (80°C) and 212°F (100°C).
  4. MAP sensor less than 46.6 kPa (13.8 in.Hg, 350 mmHg).
  5. Vehicle speed 0 mph (0 km/h).
  6. IAT SENSOR between 32°F (0°C) and 212°F (100°C).
  1. Connect the HDS to the DLC.
  2. Start the engine.
  3. Select EVAP TEST in the INSPECTION MENU with the HDS, then select the FUNCTION TEST in the EVAP TEST MENU. If the result is normal, readiness is complete. If the result is not normal, go to the next step.
  4. Check for a Temporary DTC. If there is no DTC, one or more of the enable criteria were probably not met; repeat the procedure.

Air Fuel Ratio (A/F) Sensor Monitor and Readiness Code

Note. During the procedure do not turn the ignition switch to LOCK (0) or ACC (I) during the procedure. All readiness codes are cleared when the battery is disconnected, if the DTCs have been cleared, or if the PCM is reset with the HDS.

ECT SENSOR 1 at 140°F (60°C) or more.

  1. Start the engine.
  2. Test-drive the vehicle under stop-and-go conditions with short periods of steady cruise. During the drive, decelerate (with the throttle fully closed) for 5 seconds. After about 3.5 miles (5.6 km), the readiness code should switch from incomplete to complete.
  3. Check the readiness codes screen for the AIR FUEL RATIO (A/F) SENSOR in the DTCs MENU with the HDS. If the screen shows complete, readiness is complete. If the screen shows not complete, go to the next step.
  4. Check for a Temporary DTC. If there is no DTC, the enable criteria was probably not met. Select the DATA LIST MENU. Check the ECT SENSOR in the ALL DATA LIST with the HDS. If the ECT is less than 140°F (60°C), run the engine until it is more than 140°F (60°C), then repeat the procedure.

Air Fuel Ratio (A/F) Sensor Heater Monitor Readiness Code

Note. All readiness codes are cleared when the battery is disconnected, if the DTCs have been cleared, or if the PCM is reset with the HDS.

  1. Start the engine, and let it idle for 1 minute. The readiness code should switch from incomplete to complete.
  2. If the readiness code is still not set to complete, check for a Temporary DTC. If there is no DTC, repeat the procedure.

Misfire Monitor and Readiness Code

  1. This readiness code is always set to available because misfiring is continuously monitored.
  2. Monitoring pauses, and the misfire counter resets, if the vehicle is driven over a rough road.
  3. Monitoring also pauses, and the misfire counter holds at its current value, if the throttle position changes more than a predetermined value, or if driving conditions fall outside the range of any related enable criteria.

Fuel System Monitor and Readiness Code

  1. This readiness code is always set to available because the fuel system is continuously monitored during closed loop operation.
  2. Monitoring pauses when the catalytic converter, EVAP control system, and A/F sensor monitors are active.
  3. Monitoring also pauses when any related enable criteria are not being met. Monitoring resumes when the enable criteria is again being met.

Comprehensive Component Monitor and Readiness Code

This readiness code is always set to available because the comprehensive component monitor is continuously running whenever the engine is cranking or running.

EGR Monitor and Readiness Code

Note. During the procedure do not turn the ignition switch to ACC (I) or LOCK (0) during the procedure. All readiness codes are cleared when the battery is disconnected, if the DTCs have been cleared, or if the PCM is reset with the HDS.

ECT SENSOR 1 at 176°F (80°C) or more.

  1. Connect the HDS to the DLC.
  2. Start the engine.
  3. Drive at a steady speed with the transmission in D, at 50-62 mph (80-100 km/h) or above for more than 10 seconds.
  4. With the transmission in D, decelerate from 62 mph (100 km/h) or above by completely releasing the throttle for at least 5 seconds. If the engine is stopped during this procedure, go to step 3 and do the procedure again.
  5. Check the OBD status screen for DTC P0401 in the DTCs MENU with the HDS.
  1. If it is passed, readiness is complete.
  2. If it is not passed, go to step 3 and retest.