A054

DTC A054 Rear Channel In Release Too Long (1 Of 2):

Fig 494 Code 54: Rear Channel In Release Too Long (Part 2 Of 2):

DTC A054 Rear Channel In Release Too Long:

Circuit Description:
This DTC will diagnose a motor that is energized longer than expected. This could occur if a wheel speed sensor is malfunctioning the motor does not turn or the motor wires are crossed.

Failure Condition:
DTC AO54 can be set only during an ABS stop. If the EBCM commands the rear channel in release for three seconds a malfunction exists.

Action Taken:
A DTC AO54 is stored ABS is disabled and the "ABS" indicator is turned on.

Test Description:
Number(s) below refer to circled number(s) on the diagnostic chart.
1. This step identifies a problem in the wheel speed sensor that may cause the system to be in release too long.
2. This checks for a wheel that may stick or bind because of a mechanical fault.
3. This checks to see if the motor is capable of moving and applying the hydraulic piston for the rear wheels.
4. This step ensures that the motor wiring is not crossed.
5. This isolates the fault of a "no-apply" situation to either the motor pack or the hydraulic modulator.

Diagnostic Aids:
An "intermittent" malfunction may be caused by a mechanical part of the system that sticks or binds.

The frequency of the malfunction can be checked by using the enhanced diagnostic function of the TECH 1.

Using the TECH 1 perform the hydraulic test to ensure that the total brake system is functional.

Any circuitry that is suspected of causing the intermittent complaint should be thoroughly checked for backed out terminals, improper mating, broken locks improperly formed or damaged terminals, poor terminal to wiring connections or physical damage to the wiring harness.