FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Component Tests and General Diagnostics





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