Possible Causes
WARNING: This page is about a different car, the 2004 Mercury Monterey and 2004 Ford Freestar. However, it is still accessible from the selected car via links, so may be relevant.
Air bag tone warning indicator circuit shorted to ground or open could be caused by damaged wiring harness, terminals or connectors, faulty instrument cluster or faulty RCM.
- Check for hard or intermittent DTC
Turn ignition switch to OFF position. Connect scan tool to Data Link Connector (DLC). See USING SCAN TOOL under DIAGNOSTICS. Turn ignition switch to ON position. Retrieve and record any continuous Diagnostic Trouble Codes (DTCs). See RETRIEVING FAULT CODES under DIAGNOSTICS. Perform on-demand self-test. See ON-DEMAND SELF-TEST under DIAGNOSTICS. If DTC B1892 was retrieved during on-demand self-test, fault is hard. Go to next step. If DTC B1892 was not retrieved, fault is intermittent. Go to step 6 . - Check air bag tone warning indicator circuit for short to ground
Turn ignition switch to OFF position. Disable air bag system. See DISABLING SYSTEM under DISABLING & ACTIVATING AIR BAG SYSTEM. Access RCM and disconnect connector C310A. See RESTRAINTS CONTROL MODULE (RCM) under REMOVAL & INSTALLATION. Access instrument cluster and disconnect harness connector C220A. See INSTRUMENT CLUSTER under REMOVAL & INSTALLATION. Measure resistance between ground and harness side of RCM connector C310A, terminal No. 23 (Light Blue/Pink wire, circuit No. 1083). See Figure . If resistance is more than 10 k/ohms, go to next step. If resistance is less than 10 k/ohms, repair short to ground in Light Blue/Pink wire. See WIRING DIAGRAMS . Go to step 7 . - Check air bag tone warning indicator circuit for open
Measure resistance between harness side of RCM connector C310A, terminal No. 23 and harness side of instrument cluster connector C220A, terminal No. 6 (Light Blue/Pink wire). See Figure & Figure . If resistance is less than 5 ohms, go to next step. If resistance is more than 5 ohms, repair open in Light Blue/Pink wire. Go to step 7 . - Check air bag tone warning indicator
Reconnect instrument cluster connector C220A. Turn ignition switch to ON position. Measure voltage between ground and harness side of RCM connector C310A, terminal No. 23 (Light Blue/Pink wire). If voltage is more than 10 volts, go to next step. If voltage is more than 10 volts, replace instrument cluster. Go to step 7 .NOTE: Ensure all air bag system simulators, sensor electrical connectors and RCM electrical connectors are connected prior to carrying out on-demand self-test or erroneous faults may be set. - Confirm RCM fault
Turn ignition switch to OFF position. Reconnect RCM connector C310A. Turn ignition switch to ON position. Perform on-demand self-test. If DTC B1892 was retrieved during on-demand self-test, replace RCM. Go to next step. If DTC B1892 was not retrieved during on-demand self-test, check for cause of intermittent open or short to ground in Light Blue/Pink wire. Attempt to recreate fault by flexing wire harness and cycling ignition switch frequently. Activate other systems in same wire harness. Repair any intermittent problems found. Go to next step. - 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 B1892 was retrieved during on-demand self-test, go to step 2 . If DTC B1892 was not retrieved during on-demand self-test, check for cause of intermittent short to ground or open in Light Blue/Pink wire. See WIRING DIAGRAMS . Attempt to recreate fault by flexing wire harness and cycling ignition switch frequently. Activate other systems in same wire harness. Repair any intermittent problems found. Go to next step. - 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 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.