Test A: No Communication With Abs Control Module
- Turn ignition off. Disconnect 25-pin ABS control module connector. Install EEC-IV 60-pin Breakout Box (014-00322). Turn ignition on. Using DVOM, individually measure voltage between ground and breakout box terminals No. 20 (Light Blue/Pink wire), No. 25 (Red wire) and No. 9 (Yellow/Light Green wire). If all voltages are greater than 10 volts, go to next step. If any voltage is less than 10 volts, repair appropriate wire(s). Recheck system operation.
- Turn ignition off. Measure resistance between breakout box terminal No. 8 and ground. Also, measure resistance between breakout box terminal No. 24 and ground. If both resistance measurements are less than 5 ohms, diagnose module communications network. See appropriate MODULE COMMUNICATIONS NETWORK article in ACCESSORIES & EQUIPMENT. If either resistance measurement is greater than 5 ohms, repair suspect Black wire between ABS control module and ground distribution. Recheck system operation.