LEMON Manuals: Even more car manuals for everyone
Home >> Ford >> 2000 >> Taurus LX, 3.0 2, AX4N >> Repair and Diagnosis >> External Pages >> Different car >> Section 34 (Air Bag Restraint Systems) >> Diagnostic Tests >> Test V: Left Side Air Bag Circuit Resistance High (DTC B1994) >> Possible Causes

Possible Causes

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

A left side air bag circuit high resistance could be caused by high resistance on Red/Green wire (circuit No. 30S-JA37), high resistance on Black/Green wire (circuit No. 31S-JA37), high resistance 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 B1994 was retrieved during on-demand self-test, fault is hard. Go to next step. If DTC B1994 was not retrieved, fault is intermittent. Go to step  5 .
  2. Check left side air bag

    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 B1994 is retrieved, go to next step. If DTC B1994 is not retrieved, replace left side air bag module. See SIDE AIR BAG MODULE  under REMOVAL & INSTALLATION. Go to step  6 .
    NOTE: By disconnecting RCM connector, Red/Green and Black/Green wires are shorted together by shorting bar. Do not remove shorting bar.
  3. Check left side air bag module circuit

    Turn ignition switch to OFF position. Access RCM and disconnect RCM connector C310B. See RESTRAINTS CONTROL MODULE (RCM)  under REMOVAL & INSTALLATION. Disconnect air bag simulator from left side air bag connector. Zero ohmmeter. Measure resistance between Red/Green wire and Black/Green wire on RCM side of left side air bag module harness connector. If resistance is more than one ohm, repair open in Red/Green wire or Black/Green wire. See WIRING DIAGRAMS  . Go to step  6 . If resistance is less than one ohm, go to next step.
  4. Check air bag module wiring

    Inspect all crimps, terminals, wires and connectors in circuit No. 30S-JA37 (Red/Green wire) between side air bag module connector and RCM connector C310B, terminal No. 2, and circuit No. 31S-JA37 (Black/Green wire) between side air bag module connector and RCM connector C310B, terminal No. 3. Check for pinched wires and damaged connector pin terminals. If any damage is found, repair as necessary. Go to step  6 . If no damage is found, replace RCM. Go to step  6 .
  5. Check for intermittent fault

    Turn ignition switch to OFF position. Disable air bag system. See DISABLING SYSTEM  under DISABLING & ACTIVATING AIR BAG SYSTEM. Perform on-demand self-test. If DTC B1994 was retrieved during on-demand self-test, check for causes of intermittent fault at or near left side air bag module connector. Repair any intermittent faults found and go to next step. If no intermittent faults are found, go to step  3 . If DTC B1994 was not retrieved during on-demand self-test, check for causes of intermittent high resistance on Red/Green or Black/Green 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.
  6. 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.