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.
An AIR BAG warning light that is continuously illuminated may be caused by ignition voltage less than minimum required for full RCM functionality, damaged shorting bar or camming beam, disconnected RCM, open RCM ground or ignition circuit or inoperative RCM.
- 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 step 3 . 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 RCM connector C2041A is fully connected to RCM and Red locking tab is engaged. If RCM connector C2041A is connected correctly, go to next step. If RCM connector C2041A is not connected correctly or locking tab is not engaged, connect and engage as necessary. Go to step 7 .NOTE: Shorting bars can be accessed by prying Blue cover from RCM harness connector. - Check RCM connector
Turn ignition switch to OFF position. Disable air bag system. See DISABLING SYSTEM under DISABLING & ACTIVATING AIR BAG SYSTEM. Access RCM and disconnect RCM connector C2041A. See RESTRAINTS CONTROL MODULE (RCM) under REMOVAL & INSTALLATION. Inspect component side of RCM connector C2041A for worn or damaged camming beam and/or any foreign material. See Fig 1 . Inspect harness side of RCM connector C2041A 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. Go to step 7 . - Check RCM ignition circuit for open
Turn ignition switch to RUN position. Measure voltage between sheet metal ground near RCM and harness side of RCM connector C2041A, terminal No. 2 (Violet/Orange wire, circuit No. 298). See Fig 2 . If voltage is 9-16 volts, go to next step. If voltage is not 9-16 volts, repair open in Violet/Orange wire. See WIRING DIAGRAMS . Go to step 7 . - Check ground circuit for open
Turn ignition switch to OFF position. Measure resistance between sheet metal ground near RCM and harness side of RCM connector C2041A, terminal No. 21 (Black/Orange wire, circuit No 649). If resistance is less than 10 ohms, go to next step. If resistance is more than 10 ohms, repair open in Black/Orange wire. Go to step 7 . - Check for short to ground
Measure resistance between harness side of RCM connector C2041A, terminals No. 20 (Black/Yellow wire, circuit No 608) and No. 21 (Black/Orange wire). If resistance is less than 10 k/ohms, repair short to ground in Black/Orange wire. Go to next step. If resistance is more than 10 k/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.