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 "W/Harness Inspection" procedure.

Ignition "OFF"

Disconnect Auto Defog sensor and Connect A/C control Module main harness connector.

Ignition "ON"

Measure voltage between Power terminal of Auto Defog sensor harness connector and chassis ground.

Is the measured voltage within specification?

	▶ Go to " Signal circuit Inspection" procedure .
	▶ Check for open and short to ground in harness. ▶ Repair as necessary and then go to "Verification of Vehicle Repair" procedure.

Ignition "OFF"

Disconnect Auto Defog sensor and A/C control Module main harness connector.

Measure resistance between Sensor ground(-) terminal of Auto Defog sensor harness connector and chassis ground .

Is the measured resistance within specification?

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

Ignition "OFF"

Disconnect Auto Defog sensor and A/C control Module main harness connector.

Measure resistance between Sensor Signal terminal of Auto Defog sensor harness connector and Sensor Signal terminal of A/C control Module harness connector.

Is the measured resistance within specification?

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