Test D: DTCs C1095 and C1096 -ABS Hydraulic Pump Motor Circuit Failure/Open

Pinpoint Test D: DTCs C1095 and C1096 -ABS Hydraulic Pump Motor Circuit Failure/Open
Refer to Vehicle/Diagrams, Vehicle Dynamic Systems for schematic and connector information.

Normal Operation
The operating voltage required to run the hydraulic control unit (HCU) pump motor is between 10 and 17 volts. Fused battery voltage, for the hydraulic pump motor, is supplied to the ABS module from battery junction box (BJB) fuse 17 (40A) along circuit SBB17 (RD). Ground for the hydraulic pump motor is provided through the ABS module along circuit GD122 (BK).

When the ignition key is turned to the ON position, the ABS module commands the HCU pump on for 100 ms (+1-6 ms) and is then commanded off. After 6 ms, the ABS module will read the voltage that is being generated by the HCU pump. If the voltage indicates the motor is spinning at less than 500 rpm, there may be a locked motor. The pump motor is checked for an open circuit 2 seconds after the most recent successful pump motor off command. If the pump motor feedback remains greater than 0.75 volt for more than 50 ms (+/-6 ms) after these conditions have been met, an open circuit may exist.
^ DTC C1095 ABS Hydraulic Pump Motor Circuit Failure - If a short to voltage or ground is detected, if a locked up pump motor is detected or if there is an internal failure of the ABS module, DTC C1095 will be set.
^ DTC C1096 ABS Hydraulic Pump Motor Circuit Open - If a short to voltage, a short to ground or an open is detected, if a locked up pump motor is detected or if there is an internal failure of the ABS module, DTC C1095 will be set.

This pinpoint test is intended to diagnose the following:
^ Fuse
^ Wiring, terminals or connectors
^ HCU
^ ABS module

D1-D3:

D4-D5: