Many malfunctions in the electrical system are caused by poor harness and terminals.

Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.

Thoroughly check all connectors (and connections) for looseness, bending, corrosion, contamination, deterioration, and/or damage.

Has a problem been found?

	▶ Repair as necessary and go to "Verification of vehicle Repair" procedure.
	▶ Go to "Power Circuit Inspection" procedure.

IG "OFF" and EMS box.

IG "ON"

Measure the voltage between power supply terminals of main relay harness connector and chassis ground.

Is the measured value within specification?

	▶ Go to "Control Circuit Inspection" procedure.
	▶ Repair or replace as necessary and then, go to "Verification of Vehicle Repair" procedue.

IG "OFF"

Disconnect EMS box and ECM/PCM connector.

Measure the resistance between control terminal of main relay harness connector and main relay control terminal of ECM/PCM harness connector.

Is the measured value within specification?

	▶ Go to "Control Relay Power Circuit Inspection" procedure.
	▶ Repair or replace as necessary and then, go to "Verification of Vehicle Repair" procedue.

IG "OFF"

Disconnect EMS box and ECM/PCM connector.

Measure the resistance between control relay power terminal of main relay harness connector and main relay control power terminal of ECM harness connector.

Is the measured value within specification?

	▶ Go to "System Inspection" procedure.
	▶ Repair or replace as necessary and then, go to "Verification of Vehicle Repair" procedue.