Engine Control Module: Service and Repair

PCM problem inspection procedure

1. TEST PCM GROUND CIRCUIT: Measure resistance between PCM ground and chassis ground using the backside of PCM harness connector ground as PCM side check point. If the problem is found, repair it.

Specification (Resistance)
Between terminal 1 of C230-1 connector and chassis ground : 1Ohms or less
Between terminal 2 of C230-1 connector and chassis ground : 1Ohms or less

2. TEST PCM CONNECTOR: Disconnect the PCM connector and visually check the ground terminals on PCM side and harness side for bent pins or poor contact pressure. If the problem is found, repair it.
3. If PCM problem is not found in Step 1 and 2, the PCM could be faulty. If so, replace the PCM with a new one, and then check the vehicle again. If the vehicle operates normally then the problem was likely with the PCM.
4. RE-TEST THE ORIGINAL PCM : Install the original PCM (may be broken) into a known-good vehicle and check the vehicle. If the problem occurs again in known good vehicle, replace the swapped PCM with a new one. If problem does not occur, this is intermittent problem

VIN programming procedure

VIN (Vehicle Identification Number) is a number that has the vehicle's information (Maker, Vehicle Type, Vehicle Line/Series, Body Type, Engine Type, Transmission Type, Model Year, Plant Location and so forth. When replacing an PCM, the VIN must be programmed in the PCM. If there is no VIN in PCM memory, the fault code (DTC P0630) is set.

CAUTION:
The programmed VIN cannot be changed. When writing the VIN, confirm the VIN carefully

1. Select "Vehicle" and "Engine" (For example, SEDAN 3.5L V6).




2. Select "VIN WRITING".




3. Check the PCM status.





NOTE:
- VIRGIN: VIN is not programmed
- LEARNT: VIN has been already programmed

Is the PCM status "VIRGIN"?





4. Write the VIN with cursor, function and number keys.

WARNING:
Before pressing the "ENTER" key, confirm the VIN again because the programmed VIN cannot be changed.




5. After verifying the written VIN, press the "ENTER" key.
6. Turn the ignition switch OFF, then back ON.




7. Verify the programmed VIN in the PCM memory.

Replacement

1. Turn ignition switch off.
2. Disconnect the battery (-) cable from the battery.
3. Remove the PCM cover and disconnect the PCM connector(s) (A).




4. Unscrew the PCM mounting bolts (B) and remove the PCM (C) from the air cleaner assembly.




5. Install a new PCM.

PCM mounting bolts:
9.8 - 11.8 N.m (1.0 - 1.2 kgf.m, 7.2 - 8.7 lb-ft)