Removal & Installation
The hydraulic control module, also called the Hydraulic Control Unit (HCU), is mounted to the Antilock Brake Module (ABM), also called the Controller Antilock Brake (CAB), as part of the Integrated Control Unit (ICU). The HCU controls the flow of brake fluid to the brakes using a series of valves and accumulators. A pump/motor is mounted on the HCU to supply build pressure to the brakes during an ABS stop. The ICU is located in the engine compartment, mounted to the left side body frame rail right below the master cylinder.
- Before servicing the vehicle, refer to the Precautions Section.
- Disconnect the battery negative cable.
- Raise and safely support the vehicle.
- Disconnect the pump/motor connector from Controller Antilock Brake (CAB).
- Remove the 4 screws securing CAB to Hydraulic Control Unit (HCU) half of Integrated Control Unit (ICU). Remove the CAB from the HCU.
- Pull outward on the CAB connector lock and disconnect the 24-way wiring connector.
Remove the CAB from the vehicle.
- Connect the 24-way wiring connector to the CAB and push in the connector lock.
- Align the CAB with the HCU half of the ICU, then slide the CAB up over the HCU valves.
- Install the 4 CAB mounting screws. Tighten the mounting screws to 17 inch lbs. (2 Nm).
- Connect the pump/motor connector.
- Carefully lower the vehicle.
- Connect the battery negative cable.
- Connect the DRBIII® to the vehicle to initialize the system. Check and clear any faults.
- Bleed the base and ABS brake hydraulic system. Refer to the brake bleeding procedures.
- Road test the vehicle to ensure the proper operation of the base and ABS systems.