Test C: No Communication With Generic Electronic Module
- Turn ignition switch to OFF position. Remove fuse No. 16 (15-amp) from Central Junction Box (CJB). CJB is located behind left side of instrument panel. See Figure. Turn ignition switch to RUN position. Measure voltage between ground and input side of fuse No. 16. See WIRING DIAGRAMS . If voltage is greater than 10 volts, go to next step. If voltage is less than 10 volts, repair power supply to CJB. See POWER DISTRIBUTION in appropriate SYSTEM WIRING DIAGRAMS article in ELECTRICAL. After repair, test system for normal operation.
- Turn ignition switch to LOCK position. Install fuse No. 16 in CJB. Disconnect Generic Electronic Module (GEM) harness connector C201a. GEM is located behind left side of instrument panel, attached to CJB. See Figure. Turn ignition switch to RUN position. Measure voltage between ground and GEM harness connector C201a terminal No. 4 (White/Red wire). See Fig 1. See WIRING DIAGRAMS . If voltage is greater than 10 volts, go to next step. If voltage is less than 10 volts, repair open circuit in White/Red wire between GEM and CJB. After repair, test system for normal operation.
- Turn ignition switch to LOCK position. Measure resistance between ground and GEM harness connector C201a terminal No. 6 (Black/Light Green wire). See Fig 1. See WIRING DIAGRAMS . If resistance is 5 ohms or less, repair module communications concern. See appropriate MODULE COMMUNICATION NETWORK article. If resistance is greater than 5 ohms, repair open circuit in Black/Light Green wire between GEM and ground point located on left side of engine compartment. See Figure. See GROUND DISTRIBUTIONin appropriate GROUND DISTRIBUTION article in ELECTRICAL. After repair, test system for normal operation.
Courtesy of FORD MOTOR CO.