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Home >> Ford >> 2000 >> Contour SE, 2.0 3, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 111 (Air Bag Restraint Systems) >> Diagnostic Tests >> Test Q: Left Side Air Bag Circuit Short To Battery Or Ignition (DTC B1992) >> Possible Causes

Possible Causes

WARNING: This page is about a different car, the 2002 Lincoln Blackwood. However, it is still accessible from the selected car via links, so may be relevant.

A left side air bag circuit short to battery could be caused by a short to battery in White/Light Blue wire (circuit No. 1257), short to battery in Brown/Light Blue wire (circuit No. 1258), short to battery in left side air bag module or an RCM internal fault.

  1. Check for hard or intermittent DTCs

    Turn ignition switch to OFF position. Connect scan tool to Data Link Connector (DLC). See USING SCAN TOOL  under DIAGNOSTICS. Turn ignition switch to RUN position. Retrieve and record any continuous DTCs. See RETRIEVING DIAGNOSTIC TROUBLE CODES (DTCS)  under DIAGNOSTICS. Clear continuous DTCs. See CLEARING FAULT CODES  under DIAGNOSTICS. Perform on-demand self-test. See ON-DEMAND SELF-TEST  under DIAGNOSTICS. If DTC B1992 was retrieved during on-demand self-test, fault is hard. Go to next step. If DTC B1992 was not retrieved, fault is intermittent. Go to step  6 .
  2. Check left side air bag module

    Turn ignition switch to OFF position. Disable air bag system. See DISABLING SYSTEM  under DISABLING & ACTIVATING AIR BAG SYSTEM. Turn ignition switch to RUN position. Perform on-demand self-test. If DTC B1992 is retrieved, go to step  4 . If DTC B1992 is not retrieved, go to next step.
  3. Check left side air bag module circuits for short to battery

    Turn ignition switch to OFF position. Access left side air bag module and disconnect harness connector from module. See SIDE AIR BAG MODULE  under REMOVAL & INSTALLATION. Disconnect left side air bag simulator from harness connector. Position left front seat in vehicle. DO NOT activate air bag system at this time. Connect left front seat floor harness connectors. Access RCM and disconnect both harness connectors. See RESTRAINTS CONTROL MODULE (RCM)  under REMOVAL & INSTALLATION. Turn ignition switch to RUN position. Measure voltage between ground and harness side of RCM connector C2041B, terminal No. 2 (White/Light Blue wire). See Figure . Measure voltage between ground and harness side of RCM connector C2041B, terminal No. 3 (Brown/Light Blue wire). If voltage is less than 0.2 volt in both circuits, replace left side air bag module. If voltage is more than 0.2 volt in either circuit, repair short to battery in appropriate wire. See WIRING DIAGRAMS  . Go to step  7 .
    NOTE: Due to shorting bar, short to battery can exist in either circuit.
  4. Check left side air bag seat wiring harness

    Turn ignition switch to OFF position. Access RCM and disconnect both harness connectors. See RESTRAINTS CONTROL MODULE (RCM)  under REMOVAL & INSTALLATION. Disconnect left side air bag simulator from harness connector. Measure voltage between ground and harness side of RCM connector C2041B, terminal No. 2 (White/Light Blue wire). See Figure . Measure voltage between ground and harness side of RCM connector C2041B, terminal No. 3 (Brown/Light Blue wire). If voltage is less than 0.2 volt in both circuits, go to next step. If voltage is more than 0.2 volt in either circuit, repair short to battery in appropriate wire. See WIRING DIAGRAMS  . Go to step  7 .
  5. Inspect left side air bag seat wiring harness

    Inspect all crimps, terminals, wires and connectors in circuit No. 1257 (White/Light Blue wire) between left side air bag floor harness connector and RCM connector C2041B, terminal No. 2. Inspect all crimps, terminals, wires and connectors in circuit No. 1258 (Brown/Light Blue wire) between left side air bag floor harness connector and RCM connector C2041B, terminal No. 3. Check for pinched wires and damaged connector pin terminals. If any damage is found, repair as necessary. Go to step  7 . If no damage is found, replace RCM. Go to step  7 .
  6. Check for intermittent fault

    If DTC retrieved in step  1 was an intermittent fault, check for cause of intermittent short to battery in White/Light Blue and Brown/Light Blue wires. See WIRING DIAGRAMS  . Attempt to recreate fault by flexing wire harness and cycling ignition switch frequently. Repair any intermittent problems found. Go to next step. If DTC retrieved in step  1 was not an intermittent fault, go to next step.
  7. Check for additional DTCs

    Refer to continuous DTCs recorded in step  1 . If any continuous DTCs were retrieved, go to diagnostic trouble code identification table for direction to appropriate test. See DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION  table. DO NOT clear any DTCs until all DTCs have been resolved. If no DTCs were retrieved, reconnect air bag system. Activate air bag system. See ACTIVATING SYSTEM  under DISABLING & ACTIVATING AIR BAG SYSTEM. Clear all DTCs. See CLEARING FAULT CODES  under DIAGNOSTICS.