Hydraulic Control Assembly - Antilock Brakes: Service and Repair

NOTE:
^ Always disconnect the battery Ground strap (first determine the coding for the anti-theft radio).
^ When removing brake lines, be sure the lines are marked and installed according to identification on the ABS hydraulic unit.
^ Install only original factory-made, pre-formed brake lines, or equivalent.
^ Open brake lines and connections must be sealed immediately with plugs.
^ Brake line tightening torque is: 15 Nm (11 ft 1b).
^ After having completed any work that requires opening the brake hydraulic system, bleed the system with brake filling and bleeding device US 1116 or equivalent. Service and Repair
^ In addition check the brake system with a high and low pressure test, refer to High And Low Pressure Testing. Testing and Inspection

Preparation
- Disconnect coolant expansion tank and lay to the side.
- Disconnect brake lines.
- Disconnect hydraulic unit from bracket.





Component Notes And Information
1 Cover
- Disconnect from hydraulic unit for access to relays, refer to: Fig. 1, below
2 Brake Line
- Hydraulic unit to left-front brake caliper
- Marked "VL" on hydraulic unit
3 Brake Line
- Hydraulic unit to left-rear brake caliper
- Marked "HL" on hydraulic unit
4 Brake Line
- Hydraulic unit to right-front brake caliper
- Marked "VR" on hydraulic unit
5 Brake Line
6 Brake Line
- Hydraulic unit to right rear brake caliper
- Marked "HR" on hydraulic unit
7 Brake Line
- Brake master cylinder (proportioning valve circuit) to hydraulic unit
8 Hex Nut
- Tighten to: 10 Nm (7 ft lb)
- Install hydraulic unit in bracket and secure
9 ABS Hydraulic Unit

CAUTION:
^ The ABS hydraulic unit cannot be serviced in any way except to replace the relays. Never loosen screws or bolts.
^ Replace the ABS hydraulic unit as a complete assembly only, if necessary.
^ Perform pressure testing, refer to High And Low Pressure Testing. Testing and Inspection

10 Brake Master Cylinder
- With brake booster

Procedure





Fig. 1 Relay Locations
a - Return Flow Pump Relay
b - Solenoid Valve Relay