Engine Control Module: Service and Repair

ECM Problem Inspection Procedure

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

Specification:Below 1Ohms

2. TEST ECM CONNECTOR: Disconnect the ECM connector and visually check the ground terminals on ECM side and harness side for bent pins or poor contact pressure. If the problem is found, repair it.
3. If problem is not found in Step 1 and 2, the ECM could be faulty. If so, replace the ECM with a new one, and then check the vehicle again. If the vehicle operates normally then the problem was likely with the ECM.
4. RE-TEST THE ORIGINAL ECM: Install the original ECM (may be broken) into a known-good vehicle and check the vehicle. If the problem occurs again, replace the original ECM 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 ECM, the VIN must be programmed in the ECM. If there is no VIN in ECM 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 ECM status.





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

Is the ECM status "VIRGIN"?
YES
> Go to next step 4.
NO
> END
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 ECM memory.