Diagnostic Aids

An intermittent may be caused by a poor connection, rubbed through wire insulation or a wire broken inside insulation. Check for:

• Poor Connection Or Damaged Harness

Inspect PCM harness for short to ground in IAT signal circuit, improper mating, broken locks, improperly formed or damaged terminals, poor terminal to wire connection, and damaged harness.

• Intermittent Test

Observe IAT on scan tester while moving related connectors and wiring harness with warm engine running. If failure is induced, IAT display will change to a reading of about 147°C. This may assist in isolating location of malfunction.