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.
An AIR BAG warning light that is continuously illuminated may be caused by ignition circuit damage, damaged shorting bar or other electrical connector component, disconnected Restraints Control Module (RCM) module, loss of RCM ground circuit, damaged battery or ignition circuit, inoperative RCM or AIR BAG warning light circuit shorted to ground.
- Check for continuous or on-demand self-test DTCs
Turn ignition switch to OFF position. Connect scan tool to Data Link Connector (DLC). See USING SCAN TOOL . Turn ignition switch to RUN position. Retrieve and record any continuous Diagnostic Trouble Codes (DTCs). See RETRIEVING DIAGNOSTIC TROUBLE CODES (DTCS) under DIAGNOSTICS. Perform on-demand self-test. See ON-DEMAND SELF-TEST under DIAGNOSTICS. If continuous DTCs were retrieved, go to step 3 . If on-demand DTCs were retrieved, go to diagnostic trouble code identification table for appropriate test. See DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION table. If no DTCs were retrieved, go to next step. - Check RCM connection
Turn ignition switch to OFF position. Disable air bag system. See DISABLING SYSTEM under DISABLING & ACTIVATING AIR BAG SYSTEM. Access Restraints Control Module (RCM). See RESTRAINTS CONTROL MODULE (RCM) under REMOVAL & INSTALLATION. Ensure both RCM connectors are fully connected to RCM and Red locking tabs are engaged. If RCM connectors are connected correctly, go to next step. If RCM connectors are not connected correctly or locking tabs are not engaged, connect and engage as necessary and go to step 7 . - Check RCM connector
Inspect component side of RCM connectors for worn or damaged camming beam and/or any foreign material. See Fig 1 . Inspect RCM connectors for worn, damaged or dislodged shorting bars. If camming beams and shorting bars are okay, go to next step. If camming beams and shorting bars are defective, repair or replace as necessary and go to step 7 . - Check RCM ignition circuit for open
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. Measure voltage between sheet metal ground near RCM and RCM harness connector C310A, terminal No. 2 (Pink/Orange wire). See Fig 2 . If voltage is 9-16 volts, go to next step. If voltage is not 9-16 volts, repair open in Pink/Orange wire (circuit No. 20-JA10A) and go to step 7 . See WIRING DIAGRAMS . - Check ground circuit for open
Turn ignition switch to OFF position. Measure resistance between sheet metal ground near RCM and RCM harness connector C310A, terminal No. 21 (Black/Red wire). If resistance is less than 10 ohms, go to next step. If resistance is more than 10 ohms, repair open in Black/Red wire (circuit No. 31-JA10A) and go to step 7 . - Check for short to ground
Measure resistance between RCM harness connector C310A, terminals No. 20 (Black/Green wire) and No. 21 (Black/Red wire). If resistance is less than 5 ohms, repair short to ground in Black/Green wire (circuit No. 31S-JA14) and go to next step. If resistance is more than 5 ohms, replace RCM. 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 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 and activate air bag system. See ACTIVATING SYSTEM under DISABLING & ACTIVATING AIR BAG SYSTEM. Clear all DTCs. See CLEARING FAULT CODES under DIAGNOSTICS.