Pinpoint Test B: DTCs C1095 and C1096
Anti-Lock Control
Pinpoint Tests
Pinpoint Test B: DTCs C1095 and C1096
Normal Operation
Fused battery voltage for the Hydraulic Control Unit (HCU) pump motor is supplied to the ABS module by Battery Junction Box (BJB) fuse 6 (40A) along circuit SBB06 (BN/RD). Ground for the HCU pump, coil and ABS module is provided along circuit GD163 (BK/GY). The ABS module supplies the voltage and ground for the pump motor. The 2 components are hardwired together, there are no connectors or wiring harnesses between the 2 components.
When the ignition key is turned to the ON position, the ABS module commands the HCU pump on for 100 ms (±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. If this condition is detected 4 times, DTC C1095 is set. 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, DTC C1096 is set.
- 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:
- Wiring, terminals or connectors
- Hydraulic pump motor
- ABS module
PINPOINT TEST B: DTCs C1095 AND C1096
NOTICE: Use the Flex Probe Kit for all test connections to prevent damage to the wiring terminals. Do not use standard multi-meter probes.
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B1 CHECK FOR ABS MODULE ON-DEMAND DTCs
- Connect the scan tool.
- Ignition ON.
- Using the scan tool, clear all ABS module DTCs.
- Ignition OFF.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self-Test - ABS Module.
- Retrieve and record all ABS module DTCs.
- Is DTC C1095 or C1096 present?
Yes
GO to B2.
No
For all other DTCs, GO to the ABS Module DTC Chart. Diagnostic Trouble Code Tests and Associated Procedures
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B2 CHECK THE ABS PUMP MOTOR
- Ignition ON.
- Is the ABS pump motor running all the time?
Yes
INSTALL a new ABS module and HCU. REFER to Anti-Lock Brake System (ABS) Module Service and Repair and Hydraulic Control Unit (HCU) Service and Repair. CALIBRATE the ABS module. FOLLOW the scan tool directions for the calibration procedure. CLEAR the DTCs. CARRY OUT the self-test with the brake pedal not applied.
No
GO to B3.
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B3 CHECK ABS PUMP MOTOR CONTROL OUTPUT COMMAND (ABS_MTR)
- Enter the following diagnostic mode on the scan tool: DataLogger - ABS Module.
- Toggle the ABS_MTR output command ON.
- Does the HCU pump motor run for approximately 2 seconds?
Yes
TOGGLE the ABS_MTR output command OFF. GO to B4.
No
TOGGLE the ABS_MTR output command OFF.
CLEAR the DTCs. CYCLE the ignition switch. RETRIEVE and RECORD the ABS module DTCs.
If DTC C1095 is retrieved, GO to B5.
If DTC C1096 is retrieved, INSTALL a new ABS module. REFER to Anti-Lock Brake System (ABS) Module Service and Repair. CALIBRATE the ABS module. FOLLOW the scan tool directions for the calibration procedure. CLEAR the DTCs. CARRY OUT the self-test with the brake pedal not applied.
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B4 CHECK FOR RETURNING ABS MODULE DTCs
- Using the scan tool, clear all ABS module DTCs.
- Cycle the ignition switch and test drive the vehicle above 32 km/h (20 mph).
- Enter the following diagnostic mode on the scan tool: Self-Test - ABS Module.
- Are any DTCs present?
Yes
If DTC C1096 is present, GO to B7.
If DTC C1095 is present, INSTALL a new HCU. REFER to Hydraulic Control Unit (HCU) Service and Repair. CLEAR the DTCs. REPEAT the self-test.
For all other ABS module DTCs, GO to the ABS Module DTC Chart. Diagnostic Trouble Code Tests and Associated Procedures
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. CARRY OUT the self-test with the brake pedal not applied.
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B5 CHECK THE VOLTAGE TO THE ABS MODULE FOR PUMP MOTOR ACTIVATION
- Ignition OFF.
- Disconnect: ABS Module C135.
- Measure the voltage between ABS module C135-31, circuit SBB06 (BN/RD), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to B6.
No
VERIFY BJB fuse 6 (40A) is OK. If OK, REPAIR circuit SBB06 (BN/RD). If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. CLEAR the DTCs. REPEAT the self-test. Diagrams By Number
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B6 CHECK CIRCUIT GD163 (BK/GY) FOR AN OPEN
- Ignition OFF.
- Measure the resistance between ground and:
- ABS module C135-16, circuit GD163 (BK/GY), harness side.
- ABS module C135-45, circuit GD163 (BK/GY), harness side.
- Are the resistances less than 5 ohms?
Yes
GO to B7.
No
REPAIR circuit GD163 (BK/GY). CLEAR the DTCs. REPEAT the self-test.
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B7 CHECK FOR CORRECT ABS MODULE OPERATION
- Disconnect: ABS Module C135.
- Check the ABS connector for:
- corrosion.
- pushed-out pins.
- spread terminals.
- Connect the ABS connector and make sure that it seats correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
Yes
INSTALL a new ABS module. REFER to Anti-Lock Brake System (ABS) Module Service and Repair. CALIBRATE the ABS module. FOLLOW the scan tool directions for the calibration procedure. CLEAR the DTCs. CARRY OUT the self-test with the brake pedal not applied.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. CARRY OUT the self-test with the brake pedal not applied.
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