Possible Causes
WARNING: This page is about a different car, the 2004 Ford Ranger. However, it is still accessible from the selected car via links, so may be relevant.
An invalid PAD switch resistance could be caused by damaged or inoperative PAD switch, damaged or inoperative RCM, a short to battery, damaged wiring, connectors or terminals.
- Check for hard or intermittent DTC
Turn ignition switch to OFF position. Connect scan tool to Data Link Connector (DLC). Turn ignition switch to ON position. Retrieve and record any continuous DTCs. See RETRIEVING FAULT CODES under DIAGNOSTICS. Perform on-demand self-test. See ON-DEMAND SELF-TEST under DIAGNOSTICS. If DTC B1871 was retrieved during on-demand self-test, fault is hard. Go to next step. If DTC B1871 was not retrieved, fault is intermittent. Go to step 7 . - Check White/Light Blue wire for short to battery
Turn ignition switch to OFF position. Disable air bag system. See DISABLING SYSTEM under DISABLING & ACTIVATING AIR BAG SYSTEM. Access RCM and disconnect harness connector C2041. See RESTRAINTS CONTROL MODULE (RCM) under REMOVAL & INSTALLATION. Turn ignition switch to ON position. Measure voltage between ground and RCM harness connector C2041, terminal No. 8 (White/Light Blue wire, circuit No. 1112). See Figure . If voltage is more than 0.2 volt, repair short to battery in White/Light Blue wire. See WIRING DIAGRAMS . Go to step 8 . If voltage is less than 0.2 volt, go to next step. - Check PAD switch ON position
Turn ignition switch to OFF position. Turn PAD switch to ON position. Measure resistance between ground and RCM harness connector C2041, terminals No. 8 (White/Light Blue wire) and No. 21 (Black/White wire, circuit No. 570). See Figure . If resistance is 900-1100 ohms, go to next step. If resistance is not 900-1100 ohms, go to step 2 . - Check PAD switch OFF position
Turn PAD switch to OFF position. Measure resistance between RCM harness connector C2041, terminals No. 8 (White/Light Blue wire) and No. 21 (Black/White wire). If resistance is 400-600 ohms, replace RCM. Go to step 8 . If resistance is not 400-600 ohms, go to next step. - Check White/Light Blue wire for open
Access PAD switch and disconnect harness connector C2099. See PASSENGER-SIDE AIR BAG DEACTIVATION (PAD) SWITCH under REMOVAL & INSTALLATION. Measure resistance between RCM harness connector C2041, terminal No. 8 and PAD switch connector C2099, terminal No. 6 (White/Light Blue wire). See Figure & Fig 1 . If resistance is less than 0.5 ohm, go to next step. If resistance is more than 0.5 ohm, repair open in White/Light Blue wire. Go to step 8 . - Check Black/White wire for open
Measure resistance between ground and PAD switch connector C2099, terminal No. 5 (Black/White wire). If resistance is less than 0.5 ohm, replace PAD switch. Go to step 8 . If resistance is more than 0.5 ohm, repair open in Black/White wire. Go to step 8 . - Check for intermittent fault
Turn ignition switch to OFF position. Disable air bag system. See DISABLING SYSTEM under DISABLING & ACTIVATING AIR BAG SYSTEM. Turn ignition switch to ON position. Perform on-demand self-test. If DTC B1871 was retrieved during on-demand self-test, check for intermittent fault in White/Light Blue or Black/White wire. Repair any intermittent problems found. If intermittent problems are found and repaired, go to next step. If intermittent problems are not found, go to step 2 . If DTC B1871 was not retrieved, check for cause of intermittent fault. Attempt to recreate fault by flexing wire harness and cycling ignition switch frequently. Activate systems in same wire harness. See WIRING DIAGRAMS . 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. DO NOT clear any DTCs until all DTCs have been resolved. See DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION table. If no continuous DTCs were retrieved, reconnect air bag system. Activate air bag system. See ACTIVATING SYSTEM under DISABLING & ACTIVATING AIR BAG SYSTEM. Perform system operation check. See SYSTEM OPERATION CHECK . Clear all DTCs. See CLEARING FAULT CODES under DIAGNOSTICS.