W/Harness Inspection

Air Conditioner
B1281 Humidity Sensor Short (Low) - AUTO Defog - Inspection/Repair:_:W/Harness Inspection

Terminal and Connector Inspection

1. 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.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration,or damage.
3. Has a problem been found?






Power Circuit Inspection

Check power in harness
1. Ignition "OFF"
2. Disconnect Auto Defog sensor and Connect A/C control unit main harness connector.
3. Ignition "ON"
4. Measure voltage between Power terminal of Auto Defog sensor harness connector and chassis ground.

Specification :approx. 5V




5. Is the measured voltage within specification?






Signal Circuit Inspection

Check for open in harness
1. Ignition "OFF"
2. Disconnect Auto Defog sensor and A/C control unit main harness connector.
3. Measure resistance between Sensor ground(-) terminal of Auto Defog sensor harness connector and chassis ground.

Specification :Infinity




4. Is the measured resistance within specification?





Check for open in harness
1. Ignition "OFF"
2. Disconnect Auto Defog sensor and A/C control unit main harness connector.
3. Measure resistance between Sensor Signal terminal of Auto Defog sensor harness connector and Sensor Signal terminal of A/C-ECU harness connector.

Specification :1Ohms below




4. Is the measured resistance within specification?