Test 12A: Controller Failure
NOTE:
Perform TEST 1A
before proceeding. To identify circuits, connectors and terminals referenced in testing, see WIRING DIAGRAMS
and CONNECTOR IDENTIFICATION
. After each repair, perform TEST VER-1A
to verify problem has been corrected.
- Turn ignition off. Disconnect Controller Anti-Lock Brake (CAB) connector. CAB is located behind steering rack, on left side of suspension crossmember. Inspect connector for any damaged or pushed out terminals, paying particular attention to CAB connector terminals No. 8 and 24, ground circuits (Black wires). Repair connector as necessary. If terminals are okay, go to next step.
- Using an external ohmmeter, check resistance between battery ground and CAB connector terminal No. 8, ground circuit (Black wire), and then CAB connector terminal No. 24, ground circuit (Black wire). If resistance is less than one ohm between both circuits, go to next step. If resistance is one ohm or more between either circuit, repair open Black wire(s).
- Turn ignition on. Turn all accessories on. Using an external voltmeter, check voltage between battery ground and CAB connector terminal No. 8, ground circuit (Black wire), and then CAB connector terminal No. 24, ground circuit (Black wire). If voltage is more than one volt on either circuit, repair open Black wire(s). If voltage is less than one volt on both circuits, go to next step.
- Inspect vehicle for any add-on accessories. Inspect components for proper power and ground connections. Check antenna cable routing. Repair problems as necessary. If no problems are found, replace CAB. See CONTROLLER ANTI-LOCK BRAKE under REMOVAL & INSTALLATION.