The hydraulic unit is located in the engine compartment. During operation of the anti-lock system, a pulsing may be felt at the brake pedal and a clicking heard from the hydraulic unit when the ABS system is activated.
Removal & Installation
- Disconnect the negative battery cable.
- On M50 and M52 6 cylinder engines, remove the Mass Air Flow (MAF) sensor and if equipped with cruise control, unscrew the drive motor.
- Using a clean, suitable baster or equivalent, withdraw the brake fluid from the reservoir.
- Detach the central electrical connector.
- Disconnect and remove the fluid line from the front of the master cylinder to the front of the hydraulic unit.
- Label, then disconnect the remaining fluid lines.
- Remove the suction hoses off the elbows on the pump body taking care to catch the residual brake fluid.
- On models equipped with cruise control, unscrew the carbon filter for the EVAP system.
- Remove the mounting fasteners and then the hydraulic unit.
- Installation is in reverse order of removal noting the following.
- The brake hoses must be connected in the proper location.
- The brake hydraulic system must be bled using fresh approved brake fluid.