Antilock Brake Diagnosis

Verify that the parking brake is completely released, brake warning lamp switch is not grounded and the battery has been checked (completely charged). Ensure that the contacts of the 35 pin electronic controller harness electrical connector are properly inserted and are not damaged. Check the 35 contacts of the electronic controller assembly. If there are any damaged contacts replace the electronic controller assembly. Verify that all of the following electrical connectors or wires are connected/attached:
1. 1985---87 models:
a. 7 pin plug of the valve unit.
b. 2 pin plug of the main valve.
c. 5 pin plug of the combined pressure warning switch.
d. 2 and 3 pin plug of the reservoir warning switch on 1985 models, 5 pin plug of the fluid reservoir cap on 1986---87 models.
e. 2 pin plugs on all 4 sensors.
f. 2 and 4 pin plugs on each end of the motor jumper wire, if used.
g. 2 relay plugs located near the brake fluid reservoir.
2. 1986---87 models only:
a. Ground attachment on front of hydraulic booster assembly.
b. Ground attachment in luggage compartment near the 35 pin connector.
c. Ground attachment wire from negative battery terminal to fender sheet metal, to wiring harness through the 2 pin connector.
Ensure all relays, diodes and fuse links are intact and/or properly inserted. Ensure battery cable connections are clean and tight. Check ground terminals of the electronic controller and the hydraulic unit.