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.
	▶ Go to next procedure.

Ignition "OFF"

Disconnect Ambient sensor and Cluster and A/C control unit main harness connector.

Ignition "ON"

Measure voltage between Signal(F/B) terminal of ambient sensor harness connector and chassis ground .

Is the measured voltage within specification?

	▶ Go to Next procedure.
	▶ Check for short to battery in harness. ▶ Repair as necessary and then go to "Verification of Vehicle Repair" procedure.

Ignition "OFF"

Disconnect Ambient sensor and Cluster and A/C control unit main harness connector.

Measure resistance between Signal(+) terminal of ambient sensor harness connector and Signal(+) terminal of A/C control Module harness connector.

Measure resistance between Signal(+) terminal of Cluster harness connector and Signal(+) terminal of A/C control Module harness connector.

Is the measured resistance within specification?

	▶ Go to Next procedure.
	▶ Check for open in harness. ▶ Repair as necessary and then go to "Verification of Vehicle Repair" procedure.

Ignition "OFF"

Disconnect Ambient sensor and Cluster and A/C control unit main harness connector.

Measure resistance between ground terminal of Cluster harness connector and ground terminal of A/C control Module harness connector.

Is the measured resistance within specification?

	▶ Go to Next procedure.
	▶ Check for open in harness. ▶ Repair as necessary and then go to "Verification of Vehicle Repair" procedure.