Test F: Restraint Control Module (RCM) Does Not Respond To NGS Tester
WARNING: This page is about a different car, the 1999 Lincoln Town Car. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
Depending on module configuration, with all modules connected and with ignition switch in RUN position or with engine running 2-3 volts may be present at Data Link Connector (DLC) terminal No. 7 (Light Blue/White wire). This is the International Standards Organization (ISO) 9141 diagnostic communications network circuit.
- Inspect NGS tester connector and Data Link Connector (DLC) for loose, damaged or corroded terminals. Repair connector(s) as necessary and retest system for normal operation. If connectors are okay, deactivate air bag system. See appropriate AIR BAG RESTRAINT SYSTEMS article. Disconnect Restraint Control Module (RCM) harness connector C276 located behind right side of instrument panel. Inspect harness connector for loose, damaged or corroded terminals. Repair harness connector as necessary and retest system for normal operation. If harness connector is okay, go to next step.
- Ensure ignition switch is in LOCK position. Measure resistance in Light Blue/White wire between terminal No. 7 at RCM harness connector C276 and terminal No. 7 at DLC. See Figure and Fig 1 . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or greater, repair open in Light Blue/White wire between RCM harness connector and DLC. Retest system for normal operation.
- Turn ignition switch to RUN position. Measure voltage between terminals No. 4 (Black wire) and No. 7 (Light Blue/White) at DLC. Also, measure voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Light Blue/White wire) at DLC. See Figure. If voltage is indicated at any terminals, repair Light Blue/White wire between RCM harness connector and DLC. Retest system for normal operation. If voltage is not indicated at any terminals, replace RCM and retest system for normal operation.