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

NOTE: Before disconnecting or connecting any module, ensure ignition switch is in OFF position.
  1. Turn ignition off. Disconnect 26-pin GEM connector located behind center of instrument panel. Measure resistance of Light Blue/White wire between GEM connector and Data Link Connector (DLC). 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 connector and DLC and retest system.
  2. Inspect 26-pin GEM connector for physical damage, bent terminals or corrosion. Repair or replace connector as necessary and retest system. If connector is okay, go to next step.
  3. Inspect DLC for physical damage, bent terminals or corrosion. Repair or replace connector as necessary and retest system. If connector is okay, check power and ground circuits to GEM. See GROUND DISTRIBUTION or POWER DISTRIBUTION article in WIRING DIAGRAMS. If fault is found, repair as necessary and retest system. If no fault is found, replace GEM and retest system.
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