A015

Fig. 465 Code 15: ABS Enable Contact Circuit Shorted To Battery Or Always Closed:

ABS Enable Relay & Circuit:

Circuit Description:
Ignition voltage is supplied through terminal "1" of the ABS enable relay. The EBCM then is able to energize the pull-in coil by completing the ground circuit at pin "22" of the EBCM. The magnetic field created closes the ABS enable relay contacts and allows battery voltage and current to be supplied to the EBCM, which supplies power to the motors and solenoids.

Failure Condition:
DTC A015 can be set only before the EBCM commands the relay on. This test determines if the ABS enable relay is energized when it should not be. This malfunction would not allow the ABS enable relay to remove power to the ABS system. If a second malfunction were to occur that requires the ABS enable relay to be turned off, that malfunction can not be removed if the relay can not be controlled. The malfunction must be present for three consecutive drive cycles before the DTC is set.

Action Taken:
A DTC A015 is stored. ABS is not disabled and the "ABS" indicator will not be illuminated.

Test Description:
Number(s) below refer to circled number(s) on the diagnostic chart.
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 "1" of the EBCM harness connector C2. 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 CKT 850.
5. This step identifies if the EBCM is malfunctioning.

Diagnostic Aids:
An "intermittent" malfunction may be caused by a poor connection, rubbed through wire insulation 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 TECH 1.

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.