Service Procedure

1. Raise hood, install fender covers. Leave ignition key in OFF position. Disconnect negative battery cable from battery.

RELAYS AND FUSES LOCATIONS - ILLUSTRATION 1:

2. Replace the ABS pump motor relay, and both the ABS pump motor 30 amp fuse and the ABS main 30 amp fuse. The pump motor relay will have four wires in its connector. Relay and fuses are located on the left front of dash behind the strut tower (see illustration 1).

CAUTION: Relay must be reinstalled on bracket with connector at bottom to prevent water entry. If relay bracket mounting is disturbed, bracket must be resecured to front of dash.
3. Visually inspect hydraulic pump and motor housing for any evidence of brake fluid seepage below the pressure switch. If any components require replacement, care should be taken to prevent brake fluid spillage onto the motor.
SERVICE PROCEDURE cont.

a. If any evidence of brake fluid seepage is indicated, perform the following steps as outlined in the 1987 Cadillac Service Information Manual, Section 5E, pages 5 & 6. If no seepage is indicated, proceed to Step 3b.

1) Replace the hydraulic pump and motor.

ILLUSTRATION 2:

2) Inspect pressure switch for red plastic identification band (See illustration 2). If red band is observed, the switch requires replacement. If red band is not observed, the original switch must be transferred to the replacement pump and motor.

CAUTION: FAILURE TO FULLY DEPRESSURIZE THE HYDRAULIC ACCUMULATOR BEFORE PERFORMING SERVICE OPERATIONS COULD RESULT IN INJURY TO SERVICE PERSONNEL AND DAMAGE TO PAINTED SURFACES.

b. If there is no evidence of brake fluid seepage, inspect only the pressure switch for red plastic identification band (See illustration 2). If red band is observed, the switch requires replacement. Follow pressure switch replacement procedure in 1987 Cadillac Service Information Manual, Section 5E, page 5. If red band is not observed, proceed to Step 3c.
c. If visual inspection does not indicate any parts replacement except for relay and fuses replaced in Step 2, proceed to Step 5.

4. If pressure switch is replaced, without pump arid motor replacement; check fluid level in reservoir and ensure that is is filled to the mark. Do not overfill or underfill. Connect battery cable and turn ignition key to ON position until pump motor stops. Check for brake fluid leak.

NOTE: Use only Dot 3 brake fluid from a clean, sealed container. Do riot use any fluid from a container which is wet with water. Use of Dot 5 silicone fluid is not recommended. Internal damage to the pump components may result.


SERVICE PROCEDURE cont.

a. If hydraulic pump and motor is replaced:

1) Fill reservoir with brake fluid. Connect battery cable.

2) Turn ignition key to ON position until pump motor stops.

3) Check for brake fluid leak.

4) Turn ignition key OFF and discharge accumulator. See Checking and Filling in the 1987 Cadillac Service Information Manual, Section 5E, page 4.

5) Ensure that the brake fluid reservoir is filled to the mark. Do not overfill or underfill.

5. Install a Campaign Completion Label