System Relay Ground Circuit Open

NAME OF CODE:
System Relay Ground Circuit Open

WHEN MONITORED:
The test is conducted at power-up. The system relay output voltage is tested once each 5 ms for a total period of 495 ms.

SET CONDITION:
The system relay supplies the Controller, Anti-lock Brake (CAB) solenoid drivers with B(+) power when it is commanded on by the CAB. It is turned off by the CAB to shutoff Anti-lock Brake System (ABS) functions in the event of a trouble code or a loss of B(+) to the system. The relay supplies a ground to the ABS warning lamp to illuminate the lamp when the relay is turned off. The trouble code is set if the system relay output voltage is less than 5 volts during the power up test.

POSSIBLE CAUSES:
- Open system relay normally closed contacts
- Open relay box ground circuit
- Stuck system relay normally open contact
- Loose or corroded connector terminals
- Failed relay box
- System relay control circuit shorted to B(+)