Many malfunctions in the electrical system are caused by poor harness(es) and terminals. 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.
	▶ Go to "Power Circuit Inspection" procedure.

Ignition Switch "OFF"

Refer to "Shop Manual" and remove the ECU2 30A fuse.

Measure voltage of power terminal of the ECU2 30A fuse connector and chassis ground.

Fig.1 ) ECU2 30A fuse

Is the measured value withing specification?

	▶ Go to "Ground Circuit Inspection" procedure.
	▶ Repair as necessary and go to "Verification of Vehicle Repair" procedure.

Ignition Switch "OFF"

Disconnect battery (-) cable.

Refer to "Shop Manual" and disconnect the ECM/PCM connector and the engine room junction box connector.

Measure resistance between Pin No. 7(engine control relay) of the engine room junction box and Pin No. 47(engine control relay) of the ECM/PCM connector and chassis ground.

Is the measured value within specification?

	▶ If no problems were found with the circuits or connectors, Replace the main relay and go to "Verification of Vehicle Repair" procedure.
	▶ Repair as necessary and go to "Verification of Vehicle Repair" procedure.