Diagnostic Aids

An intermittent problem can be caused by misrouted harness, rubbed through wire insulation or broken wire inside insulation. Check and repair wiring as necessary. If wiring is okay, connect a DVOM between signal circuit terminal at ECT sensor harness connector and ground circuit terminal at PCM harness connector. Observe DVOM and bend, wiggle and twist related connectors and wiring harness. If a fault is induced, resistance reading will change.