Many malfunctions in the electrical system are caused by poor connection. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.

Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration,or damage.

Has a problem been found?

	▶ Repair as necessary and go to "Verification of Vehicle Repair" procedure.
	▶ Perform following procedures

Ignition "OFF".

Disconnect Engine PCM connector.

Ignition "ON"

Measure voltage between signal terminal of PCM harness connector and chassis ground.

Is the measured voltage within specification ?

	▶ Go to "Component Inspection" procedure.
	▶ Check open or short to signal circuit and then, go to "Verification of Vehicle Repair" procedure.