Test E: No Communication With Generic Electronic Module
- Turn ignition switch to OFF position. On 2.5L engines, disconnect 18-pin Generic Electronic Module (GEM) harness connector C201B. On all other engines, disconnect 20-pin GEM harness connector C2100A. GEM is located behind center of instrument panel. Turn ignition switch to RUN position. On 2.5L engines, measure voltage between ground and GEM harness connector C201B terminals No. 3 (Gray/Yellow wire), No. 12 (Black/Pink wire), No. 13 (Red/Black wire) and No. 16 (White/Yellow wire). See Figure
. Voltages should be more than 10 volts. On all other engines, measure voltage between ground and GEM harness connector C2100A terminals No. 1 (White/Yellow wire), No. 15 (Red/Yellow wire) and No. 17 (Black/Pink wire). See Figure
. Voltages should be more than 10 volts. If voltages are as specified, go to next step. If voltages are not as specified, repair open or short to ground in appropriate wire(s) between GEM and central junction box.
- Turn ignition switch to OFF position. On 2.5L engines, disconnect 26-pin GEM harness connector C201A. Measure resistance in Black/Orange wire between ground and GEM harness connector C201A terminal No. 26. See Fig 1
. Resistance should be less than 5 ohms. On all other engines, measure resistance in Black/Orange wire between ground and GEM harness connector C2100A terminal No. 2. Resistance should be less than 5 ohms. If resistance is as specified, repair module communications concern. See appropriate testing in MODULE COMMUNICATIONS NETWORK - RANGER article. If resistance is not as specified, repair open in Black/Orange wire between GEM and ground. Ground point is located behind left side of instrument panel.
Courtesy of FORD MOTOR CO.