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DTC 14

Code 14: ABS Relay Contact Circuit Open (part 1 Of 3).:




DTC 14 ABS Relay Contact Circuit Open (2 Of 3):




Code 14: ABS Relay Contact Circuit Open (Part 3 Of 3).:




DTC 14 ABS Relay Contact Circuit Open:







Circuit Description:
Ignition voltage is supplied through terminal "C2" of the ABS relay. The EBCM then is able to energize the pull-in coil by completing the ground circuit at connector "C1", terminal "A11" of the EBCM. The magnetic field created closes the ABS relay contacts and allows battery voltage and current to be supplied to the EBCM, which supplies power to the motors and solenoids.

DTC Will Set When:
DTC 14 can be set anytime after the EBCM commands the ABS relay "ON" (the relay is first commanded "ON" during the three second bulb check). This test monitors the availability of current and 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 amber ABS warning lamp is turned "ON." The red "BRAKE" warning lamp is turned "ON" if the hydraulic modulator rear piston is not in the "HOME" position.

DTC Chart Test Description:
Number(s) below refer to circled number(s) on the diagnostic chart.
1. Checks to see if DTC 16 is also set as current or history. if DTC 16 is also set, proceed to that chart first.
2. Verifies that the malfunction is currently present.
3. Verifies that the relay can be turned "ON" and provide voltage to the EBCM.
4. Checks for high resistance in the switched battery circuit from the ABS relay to the EBCM.
5. Checks for high resistance in the switched battery circuit from the battery to the ABS relay.
6. Checks for high resistance in the ABS relay contacts.
7. Checks for poor terminal contact or corrosion at the connectors.
8. Determines if the EBCM is the cause of the malfunction.
9. Checks for high resistance in the entire ABS relay coil circuit.
10. Verifies proper battery condition.
11. Verifies proper voltage is available at the ABS relay.
12. Checks for an open in the switched battery circuit from the relay to the EBCM.
13. Verifies the condition of the ABS relay.
14. Checks for proper resistance of the ABS relay coil.
15. Checks for high resistance in the ABS relay control circuit between the ABS relay and the EBCM.
16. Checks for high resistance in the ABS relay control circuit between the battery and the ABS relay.

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.

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