Controller Failure

Test 13-16:

Symptom:
CONTROLLER FAILURE

When Monitored and Set Condition:
CONTROLLER FAILURE

When Monitored: Ignition on. Two microprocessors, internal to the CAB, calculate the wheel speed independently of each other then compare the results.

Set Condition: If the values that each microprocessor calculate for wheel speed differ by more than 1.5% for more than 70 milliseconds (MS), the Diagnostic Trouble Code (DTC) is set.

POSSIBLE CAUSES
GROUND CIRCUIT CONNECTION POOR
GROUND CIRCUIT OPEN
CAB DEFECTIVE - GROUND CIRCUIT OPEN
GROUND CIRCUIT RADIO FREQUENCY INTERFERENCE