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A014

Diagnostic Chart:




Wiring Diagram:






CIRCUIT DESCRIPTION
Ignition voltage is supplied through terminal "A2" of the ABS enable relay. The Electronic Brake Control Module (EBCM) then is able to energize the pull-in coil by completing the ground circuit at terminal "22" of the EBCM. The magnetic field created closes the 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 A014 can be set anytime after the EBCM commands the enable relay "ON" (the relay is first commanded "ON" during the three second bulb check). This test monitors the availability of current/voltage to the motors and solenoids. This malfunction indicates voltage is not available and would therefore not allow ABS operation if required.

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 checks to see if DTC A016 is also set as current or history. If DTC A016 is also set, proceed to that chart first.
2. This step verifies that the malfunction is currently present.
3. This step verifies that voltage is available at the relay coil and at the relay switch.
4. This step checks to see if a malfunctioning EBCM is the cause of DTC A014 being set.
5. This step checks for an open in the switched battery input circuit.
6. This step checks for an open in the relay control circuit.
7. This step determines whether the malfunction is intermittent or caused by a malfunctioning relay.
8. This step determines if the low voltage condition was caused by an open in the voltage feed circuits to the relay or by a vehicle charging system malfunction.
9. This step checks for a possible intermittent malfunction.

DIAGNOSTIC AIDS
An "Intermittent" problem may be caused by a poor connection, rubbed through wire insulation, or a wire that is broken inside the insulation.

The frequency of the problem can be checked by using the enhanced diagnostic function of the Tech 1.

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.

VIBRATION, TEMPERATURE EFFECTS
Check for vibration effects by performing the relay test function of the Tech 1. With the relay test commanded "ON," lightly tap the top and sides of the relay while monitoring relay voltage. If the relay voltage changes significantly, replace the relay.

If DTC A014 only sets when the vehicle is initially started in cold ambient conditions (temperature less than 32°F - 0°C), replace the relay.