Harness Check
- If PCM is found to be faulty during self-diagnostics testing, perform following steps to confirm diagnosis. Most components are incorrectly diagnosed due to faulty electrical connectors or poor connections between component and vehicle. Sometimes, simply disconnecting and connecting a component connector will provide a good electrical connection.
- Inspect PCM 60-pin harness connector, harness and PCM contact pins for corrosion, bent pins, missing pins, spread terminals and broken wires. Clean, repair or replace as necessary. Check all components, harness and connectors in suspected circuit.
- Connect PCM 60-pin harness connector to PCM, and retest system using Diagnostic Readout Box (DRB) or similar scan tool. See appropriate TESTS W/CODES
article in the ENGINE PERFORMANCE section below. If vehicle does not pass test and fails with same message, replace PCM.