Possible Causes
A left seat belt buckle switch open circuit fault could be caused by damaged wiring, terminals or connectors, faulty seat belt buckle switch or a 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. 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 B2432 was retrieved during on-demand self-test, fault is hard. Go to next step. If DTC B2432 was not retrieved, fault is intermittent. Go to step 8 . - Check circuit for open between left front seat & RCM
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 under REMOVAL & INSTALLATION. Disconnect left front seat floor connector C311. Measure resistance between harness side of RCM connector C310A, terminal No. 5 and vehicle harness side of front seat floor connector, terminal No. 10 (Brown/Light Blue wire, circuit No. 85). 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 Brown/Light Blue wire. See WIRING DIAGRAMS . Go to step 9 . - Check circuit for open between left front seat & RCM
Measure resistance between harness side of RCM connector C310A, terminal No. 9 and vehicle harness side of left front seat floor connector C311, terminal No. 4 (Tan/Black wire, circuit No. 1558). If resistance is less than 0.5 ohm, go to next step. If resistance is more than 0.5 ohm, repair open in Tan/Black wire. Go to step 9 . - Check circuit for open between left front seat & seat belt buckle switch
Disconnect left front seat belt buckle switch connector. Measure resistance in Brown/Light Blue wire between seat harness side of left front seat floor connector C311, terminal No. 10 and seat harness side of left front seat belt buckle switch connector. See Fig 2 . If resistance is less than 0.5 ohm, go to next step. If resistance is more than 0.5 ohms, repair open in Brown/Light Blue wire. Go to step 9 . - Check circuit for open between left front seat switch
Measure resistance in Tan/Black wire between seat harness side of left front seat floor connector C311, terminal No. 4 and seat harness side of left front seat belt buckle switch connector. If resistance is less than 0.5 ohm, go to next step. If resistance is more than 0.5 ohms, repair open in Tan/Black wire. Go to step 9 . - Check seat belt buckle switch
Reconnect RCM connector C310A. Install known-good seat belt buckle. See SEAT BELT BUCKLE under REMOVAL & INSTALLATION. Position left front seat in vehicle. Reconnect left front seat floor connector C311. Turn ignition switch to RUN position. Perform on-demand self-test. If DTC B2432 was retrieved during on-demand self-test, go to next step. If DTC B2432 was not retrieved, fault is corrected. Go to step 9 .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. Reinstall original seat belt buckle. Turn ignition switch to RUN position. Perform on-demand self-test. If DTC B2432 was retrieved during on-demand self-test, replace RCM. Go to step 9 . If DTC B2432 was not retrieved during on-demand self-test, fault is corrected. Go to step 9 . - 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 B2432 was retrieved during on-demand self-test, go to step 2 . If DTC B2432 was not retrieved during on-demand self-test, check for cause of intermittent fault. Attempt to recreate fault by flexing wire harness and cycling ignition switch frequently. 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.
Courtesy of FORD MOTOR CO.
