A052

Diagnostic Chart:

Wiring Diagram:

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, the left front solenoid mechanically fails open, or the motor wires are crossed.

FAILURE CONDITION
DTC A052 can be set only during an ABS stop. If the Electronic Brake Control Module (EBCM) commands the left front channel in release for three seconds, a malfunction exists.

ACTION TAKEN
A malfunction DTC is stored, ABS is disabled and the ABS indicator lamp is turned "ON."

TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. This step identifies a problem in a wheel speed sensor that may cause the system to be in release too long.
2. This step identifies a motor as being failed or wired incorrectly.
3. This step checks for a solenoid that may have mechanically failed open.
4. If Step 3 has failed, this serves to isolate the cause of the hydraulic problem, to either the solenoid or the ABS hydraulic modulator assembly.
5. This step prepares the hydraulic modulator/motor pack assembly for separation.
6. This step determines whether a malfunctioning motor pack or hydraulic modulator is the reason for DTC A052 being set.

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. DTC A052 may fail if on ice and steering wheel is turned to lock during braking. Using the Tech 1, perform hydraulic test to ensure total brake system is functional.

Any circuitry, that is suspected as 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.