Antilock Braking System (ABS)

DTC 17 BPMV Pump Motor Relay Contact Circuit Open:

CIRCUIT DESCRIPTION
The ABS/TCS receives power from three circuits. CKT 642 supplies battery power to the pump motor. CKT 342 supplies battery power to the solenoid valves, the EBCM/EBTCM, and the coil of the pump motor relay. CKT 641 supplies battery power to initialize controller operations. It also supplies power to the solenoid valve relay.

DTC WILL SET WHEN
The Power Distribution system does not supply battery voltage to CKT 642. Fuse 1 (ABS Motor) is open. CKT 642 has a wiring problem, terminal corrosion, or poor connections. There is an internal malfunction in the EBCM/EBTCM or the BPMV.

ACTION TAKEN
A malfunction DTC is stored, ABS/TCS is disabled and the "ANTILOCK" and "TRACTION OFF" Indicator lamps are turned "ON."

DTC CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. Checks the ABS MOTOR fuse.
2. Determines if a short to ground in CKT 642 caused fuse to open.
3. Checks for an open in CKT 642.
4. Determines proper voltage is supplied to the EBCM/EBTCM.
5. Checks if the ABS Motor fuse opens again after replacement.
6. Checks for a short to ground in CKT 642.
7. Checks for an internal short to ground in the BPMV.

DIAGNOSTIC AIDS
Possible causes:
- Intermittent short to GND in CKT 642.
- Open in Pump Motor Power input circuit.

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.