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Test B: Generic Electronic Module (Gem)/Central Timer Module (CTM) Does Not Respond To NGS Tester

  1. Turn ignition off. Disconnect GEM/CTM 26-pin connector C280 located behind center of instrument panel. See Figure. Inspect connector for physical damage, bent terminals or corrosion. Repair connector as necessary and retest system for normal operation. If connector is okay, go to next step.
  2. Measure resistance of Light Blue/White wire between terminal No. 25 at GEM/CTM connector and terminal No. 7 at Data Link Connector (DLC). See Figure and Fig 1. If resistance is less than 5 ohms, replace GEM/CTM and retest system for normal operation. If resistance is 5 ohms or more, repair open in Light Blue/White wire between GEM/CTM connector and DLC. Retest system for normal operation.
Fig 1: Identifying GEM/CTM 26-Pin Connector Terminals (RAP Module Is Similar)
G97A28803Courtesy of FORD MOTOR CO.
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