C Short-Air Compressor Relay Circuit

Short-Air Compressor Relay Circuit

PINPOINT TEST C: SHORT-AIR COMPRESSOR RELAY CIRCUIT:

PINPOINT TEST C: SHORT-AIR COMPRESSOR RELAY CIRCUIT (Continued):

The Control Module has detected a short in the circuit used to activate the air compressor relay. There are five possible causes of this short:
1. Battery Positive Voltage (B+) power supply circuit is shorted to ground.
2. Vehicle wiring harness has B+ power supply circuit and ground return circuit in wrong location.
3. Air compressor relay is inoperative.
4. Air suspension Control Module is inoperative.
5. The air compressor relay has a diode in it. When current is applied in the reverse direction this diode will act like a short. Because all ohmmeters do not have the same positive and negative polarity the following test procedures are being used to locate the cause of the short.