03 Return Air Sensor Short Circuit (Check Alarm)

Thermo King Alarm Code

Description	Corrective Action
Return Air Sensor Short Circuit (Check Alarm) Sensor circuit resistance lower than 200 ohms. Temperature above 80C (176F). Indicates: Short circuit to sensor Defective or wrong sensor Defective relay board Defective cable No.1 Defective controller	Check sensor resistance between pins 3and 4 on plug J15. Resistance must be 2,000 ohms at 25C (77F). Check cable No.1 between controller and relay board.