DTC A015: ABS Enable Relay Circuit Shorted to Batt. or Closed

ABS ENABLE RELAY CIRCUIT SHORTED TO BATTERY OR ALWAYS CLOSED





Circuit Description
Ignition voltage is supplied through terminal 85 of the ABS enable relay socket. The electronic brake control module (EBCM) then is able to energize the pull-in coil by completing the ground circuit at pin All of the EBCM. The magnetic field created closes the ABS enable relay contacts and supplies battery voltage and current to the EBCM, which supplies power to the motors.

Diagnosis
This test determines a situation in which switched battery power is present at the EBCM when the relay is deenergized due to an ABS failure. A fault exists if for 4seconds; the switched battery voltage is greater than 4.5 volts. This code may accompany the following codes:
A058 LF Motor (high side) short to battery,
A063 RF Motor (high side) short to battery.
A064 RA Motor (high side) short to battery.
A077 LF Solenoid short to battery.
A081 RF Solenoid short to battery.
This is due to the electrical connection of the above circuits to the relay. If code A0 15 is detected along with the above codes, troubleshoot the above codes first.

Cause(s)
- There are malfunctioning relay contacts (contacts are closed all the time).
- A solenoid or motor circuit has shorted to battery.
- A short to battery is present on the switched battery circuit.
- The EBCM is faulty.

Fail Action
Set history code.
A DTC A015 is stored. The ABS is not disabled, but the ABS indicator will flash to indicate that a malfunction exists.

Test Description
The number(s) below refer to step(s) on the diagnostic table.
1. This step indicates that the EBCM is capable of controlling the ABS enable relay as commanded.
2. This step checks for voltage at terminal C7 of the EBCM harness connector J2. If voltage is present, the malfunction exists in the ABS enable relay and/or its circuitry.
3. This test checks for a short to ground in the ABS enable relay control circuit.
4. This step checks for a short to voltage in circuit RED.
5. This step identifies if the EBCM is malfunctioning.

Diagnostic Aids
An intermittent malfunction may be caused by a poor connection, wire insulation that has been rubbed through, or a wire that is broken inside the insulation.
The frequency of the malfunction can be checked by using the enhanced diagnostic function of the scan tool as described in "Scan Tool Diagnostics." Scan Tool Diagnostics
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.





DIAGNOSTIC TROUBLE CODE (DTC) A015