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 Auto defogger humidity Potentiometer(actuator) and A/C control module main harness connector.

Measure resistance between Signal(F/B) terminal of Auto Defog actuator harness connector and Signal(F/B) terminal of A/C control module harness connector.

Is measured value within specification?

	▶ Perform following procedures.
	▶ Check for open in harness. ▶ Repair as necessary and then go to "Verification of Vehicle Repair" procedure.

Ignition "OFF"

Disconnect Auto defogger humidity Potentiometer(actuator) and A/C control module main harness connector.

Measure resistance between Signal(F/B) terminal of Auto defogger humidity Potentiometer(actuator) harness connector and chassis ground.

Is measured value within specification?

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

Ignition "OFF"

Disconnect Auto defogger humidity Potentiometer(actuator) and Connect A/C control module main harness connector.

Ignition "ON"

Measure voltage between Sensor REF(5V) terminal of Auto defogger humidity Potentiometer(actuator) harness connector and chassis ground.

Is measured value within specification?

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