Test B: Generic Electronic Module/Central Timer Module (Gem/CTM) Does Not Respond To NGS Tester
CAUTION:
Disconnect battery before disconnecting or connecting GEM/CTM. Failure to do so may result in GEM/CTM storing erroneous codes and/or erratic operation of GEM/CTM.
NOTE:
GEM is supplied on vehicles equipped with 4-wheel drive and/or power windows. CTM is supplied on vehicles not equipped with either 4-wheel drive or power windows.
- Turn ignition off. Disconnect GEM/CTM 26-pin connector C221 located behind center of instrument panel. Inspect GEM/CTM connector C221 and Data Link Connector (DLC) for physical damage, bent terminals or corrosion. Repair connectors as necessary and retest system for normal operation. If connectors are okay, go to next step.
- Measure resistance of Light Blue/White wire between GEM/CTM connector C221 terminal No. 25 and DLC terminal No. 7. 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 and DLC and retest system for normal operation.