Test B: No Communication With Generic Electronic Module
- Turn ignition switch to OFF position. Disconnect Generic Electronic Module (GEM) 22-pin harness connector T-201a. Turn ignition switch to RUN position. Measure voltage between ground and GEM harness connector T-201a, terminal No. 12 (Orange/Light Green wire). See Fig 1
. Measure voltage between ground and GEM harness connector T-201a, terminal No. 13 (Red/Yellow wire). If both voltages are 10 volts or more, go to next step. If either voltage is less than 10 volts, repair open in Orange/Light Green wire or Red/Yellow wire. See WIRING DIAGRAMS
.
- Turn ignition switch to OFF position. Disconnect GEM 26-pin harness connector T-201b. GEM is located behind center of instrument panel. Turn ignition switch to RUN position. Measure voltage between ground and GEM harness connector T-201b, terminal No. 26 (Black/White wire). See Fig 2
. If voltage is 10 volts or more, go to next step. If voltage is less than 10 volts, repair open in Black/White wire. See WIRING DIAGRAMS
.
- Turn ignition switch to OFF position. Ensure GEM harness connector T-201a is still disconnected. Turn ignition switch to RUN position. Measure voltage between ground and GEM harness connector T-201a, terminal No. 1 (Black/Pink wire). If voltage is 10 volts or more, go to next step. If voltage is less than 10 volts, repair open in Black/Pink wire. See WIRING DIAGRAMS
.
- Turn ignition switch to OFF position. Measure resistance between ground and GEM harness connector T-201b, terminal No. 12 (Black wire). If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in Black wire between GEM and ground. See WIRING DIAGRAMS
. Ground point is located on floor below driver's seat.
- Measure resistance between ground and GEM harness connector T-201a, terminal No. 2 (Black/White wire). If resistance is less than 5 ohms, repair module communications concern. See MODULE COMMUNICATIONS NETWORK - TRIBUTE article. If resistance is 5 ohms or more, repair open in Black/White wire between GEM and ground. See WIRING DIAGRAMS
. Ground point is located behind center of instrument panel, near GEM.
Courtesy of FORD MOTOR CO.
Courtesy of FORD MOTOR CO.