Hydraulic Control Assembly - Antilock Brakes: Service and Repair

Removal Procedure





1. Disconnect the negative battery cable.
2. Disconnect the 26- or 31 -pin ABS wiring harness connector from its socket on the E8CM.
3. Cover the connector and the socket with shop cloths to protect them from brake fluid.





Notice: Take care not to allow air into the hydraulic unit or into the brake pipes from the master cylinder. If air gets into the hydraulic unit, it will require a bleeding procedure using a scan tool programmed for the ABS 5.3 system. As long as no air enters the hydraulic unit, a simple bleeding procedure is all the system will require.

4. Remove the brake pipes from the hydraulic unit. It may be necessary to loosen the brake pipe nuts on the master cylinder to allow for moving those pipes out of the way.
5. Loosen the mounting nuts on the hydraulic unit.
6. Move the brake pipes aside far enough to allow for lifting the ABS 5.3 unit out of the mounting bracket.
7. Tighten the brake pipe nuts on the master cylinder to avoid leaking brake fluid.
8. Cap the brake pipes.

Installation Procedure





1. Insert the ABS 5.3 hydraulic unit into its mounting bracket and install the nuts.
Tighten the ABS 5.3 mounting nuts to 10 Nm (89 inch lbs.).
2. Remove the screw plugs and install all of the hydraulic brake pipes.
Tighten the brake pipe nuts to 16 Nm (12 ft. lbs.).
3. Connect the 26- or 31 -pin wiring harness connector.
4. Connect the negative battery cable.
5. Bleed the hydraulic system.