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Test B: Generic Electronic Module Does Not Respond To NGS Tester

CAUTION: Disconnect battery before disconnecting or connecting Generic Electronic Module (GEM). Failure to do so may result in GEM storing erroneous codes and/or erratic operation of GEM.
  1. Turn ignition switch to OFF position. Disconnect 20-pin Generic Electronic Module (GEM) harness connector C201A (2.5L engine) or C2100A (all other engines), located behind center of instrument panel. See Fig 1 . Inspect GEM harness connector C201A or C2100A for physical damage, bent terminals or corrosion. Repair GEM harness connector C201A or C2100A as necessary and retest system for normal operation. If GEM harness connector C201A or C2100A is okay, go to next step.
  2. On 2.5L engines, measure resistance in Light Blue/White wire between GEM harness connector C201A terminal No. 25 and Data Link Connector (DLC) terminal No. 7. On all other engines, measure resistance in Light Blue/White wire between GEM harness connector C2100A terminal No. 3 and DLC terminal No. 7. See Figure and Fig 2 . If resistance is less than 5 ohms, go to next step. If resistance is more than 5 ohms, repair open in Light Blue/White wire between GEM and DLC and retest system for normal operation.
  3. Disconnect all GEM harness connectors. Inspect GEM harness connectors for physical damage, bent terminals or corrosion. Repair GEM harness connectors as necessary. Reconnect all GEM harness connectors. Retest system for normal operation. If problem still exists, replace GEM. Perform DATA LINK DIAGNOSTIC TEST  . If problem no longer exists, system is okay at this time.
Fig 1: Locating Generic Electronic Module Harness Connector C201A Or C2100A
G00041052Courtesy of FORD MOTOR CO.
Fig 2: Identifying Generic Electronic Module Harness Connector C201A Or C2100A Terminals
G95H34923Courtesy of FORD MOTOR CO.