LEMON Manuals: Even more car manuals for everyone
Home >> Ford >> 2000 >> Contour SE, 2.0 3, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 270 (Air Bag Restraint Systems) >> Diagnostic Tests >> Test V: Cross Link Between Firing Loops (DTC B 2792) >> Possible Causes

Possible Causes

WARNING: This page is about a different car, the 2004 Ford Econoline. However, it is still accessible from the selected car via links, so may be relevant.

Cross link between firing loops can be caused by faulty wiring or faulty RCM.

  1. Check for continuous & on-demand DTCs

    Turn ignition switch to OFF position. Disable air bag system. See DISABLING SYSTEM  under DISABLING & ACTIVATING AIR BAG SYSTEM. Retrieve and record any continuous or on-demand DTCs. See RETRIEVING FAULT CODES  . Clear all DTCs. See CLEARING FAULT CODES  under DIAGNOSTICS. Cycle ignition switch to OFF position and then to ON position. Retrieve and record any continuous or on-demand DTCs. If DTC B2792 and B1938 are retrieved, go to next step. If DTC B2792 and B1879 are retrieved, go to step  3 . If DTC B2792 and B1883 are retrieved, go to step  4 . If DTC B2792 was not retrieved with DTCs B1938, B1879 or B1883, fault is intermittent. Go to step  7 .

  2. Check passenger-side air bag circuits for short to driver-side air bag circuits

    Turn ignition switch to OFF position. Access RCM and disconnect harness connector C310A. See RESTRAINTS CONTROL MODULE (RCM)  under REMOVAL & INSTALLATION. Disconnect air bag simulators from driver- and passenger-side air bag harness connectors. Measure resistance between harness side of RCM connector C310A, terminal No. 3 (Light Blue/Orange wire, circuit No. 607) and No. 1 (Gray/Orange wire, circuit No. 614). See Figure . Measure resistance between harness side of RCM connector C310A, terminal No. 3 (Light Blue/Orange wire) and No. 2 (Gray/White wire, circuit No. 615). Measure resistance between harness side of RCM connector C310A, terminal No. 4 (Pink/Black wire, circuit No. 616) and No. 1 (Gray/Orange wire). Measure resistance between harness side of RCM connector C310A, terminal No. 4 (Pink/Black wire) and No. 2 (Gray/White wire). If resistance is more that 10 k/ohms in all circuits, go to step  6 . If resistance is less that 10 k/ohms in any circuit, repair short between appropriate wires. See WIRING DIAGRAMS  . Go to step  8 .

  3. Check left front seat belt pretensioner circuits for short to driver- or passenger-side air bag circuits

    Turn ignition switch to OFF position. Access RCM and disconnect harness connectors C310A and C310B. See RESTRAINTS CONTROL MODULE (RCM)  under REMOVAL & INSTALLATION. Disconnect left front seat belt pretensioner harness connector. Disconnect air bag simulators from driver- and passenger-side air bag harness connectors. Measure resistance between harness side of RCM connector C310B, terminal No. 24 (Light Green/Red wire, circuit No. 1079) and harness side of RCM connector C310A, terminal No. 1 (Gray/Orange wire, circuit No. 614). See Figure . Measure resistance between harness side of RCM connector C310B, terminal No. 24 (Light Green/Red wire) and harness side of RCM connector C310A, terminal No. 2 (Gray/White wire, circuit No. 615). Measure resistance between harness side of RCM connector C310B, terminal No. 23 (Light Green/Black wire, circuit No. 1080) and harness side of RCM connector C310A, terminal No. 1 (Gray/Orange wire). Measure resistance between harness side of RCM connector C310B, terminal No. 23 (Light Green/Black wire) and harness side of RCM connector C310A, terminal No. 2 (Gray/White wire). Measure resistance between harness side of RCM connector C310B, terminal No. 24 (Light Green/Red wire) and harness side of RCM connector C310A, terminal No. 3 (Light Blue/Orange wire, circuit No. 607). Measure resistance between harness side of RCM connector C310B, terminal No. 24 (Light Green/Red wire) and harness side of RCM connector C310A, terminal No. 4 (Pink/Black wire, circuit No. 616). Measure resistance between harness side of RCM connector C310B, terminal No. 23 (Light Green/Black wire) and harness side of RCM connector C310A, terminal No. 3 (Light Blue/Orange wire). Measure resistance between harness side of RCM connector C310B, terminal No. 23 (Light Green/Black wire) and harness side of RCM connector C310A, terminal No. 4 (Pink/Black wire). If resistance is more than 10 k/ohms in all circuits, go to step  6 . If resistance is less that 10 k/ohms in any circuit, repair short between appropriate wires. See WIRING DIAGRAMS  . Go to step  8 .

  4. Check left front seat belt pretensioner circuits for short to right front seat belt pretensioner circuits

    Turn ignition switch to OFF position. Access RCM and disconnect harness connector C310B. See RESTRAINTS CONTROL MODULE (RCM)  under REMOVAL & INSTALLATION. Disconnect left and right front seat belt pretensioner harness connectors. Measure resistance between harness side of RCM connector C310B, terminal No. 24 (Light Green/Red wire, circuit No. 1079) and harness side of RCM connector C310B, terminal No. 6 (Yellow/Red wire, circuit No. 1081). Measure resistance between harness side of RCM connector C310B, terminal No. 23 (Light Green/Black wire, circuit No. 1079) and harness side of RCM connector C310B, terminal No. 6 (Yellow/Red wire). Measure resistance between harness side of RCM connector C310B, terminal No. 24 (Light Green/Red wire) and harness side of RCM connector C310B, terminal No. 5 (Light Blue/Black wire, circuit No. 1082). Measure resistance between harness side of RCM connector C310B, terminal No. 23 (Light Green/Black wire) and harness side of RCM connector C310B, terminal No. 5 (Light Blue/Black wire). If resistance is more than 10 k/ohms in all circuits, go to step  6 . If resistance is less that 10 k/ohms in any circuit, repair short between appropriate wires. See WIRING DIAGRAMS  . Go to step  8 .

  5. Check right seat belt pretensioner circuits for short to driver- or passenger-side air bag circuits

    Turn ignition switch to OFF position. Access RCM and disconnect harness connectors C310A and C310B. See RESTRAINTS CONTROL MODULE (RCM)  under REMOVAL & INSTALLATION. Disconnect left front seat belt pretensioner harness connector. Disconnect air bag simulators from driver- and passenger-side air bag harness connectors. Measure resistance between harness side of RCM connector C310B, terminal No. 6 (Yellow/Red wire, circuit No. 1081) and harness side of RCM connector C310A, terminal No. 1 (Gray/Orange wire, circuit No. 614). See Figure . Measure resistance between harness side of RCM connector C310B, terminal No. 6 (Yellow/Red wire) and harness side of RCM connector C310A, terminal No. 2 (Gray/White wire, circuit No. 615). Measure resistance between harness side of RCM connector C310B, terminal No. 5 (Yellow/Black wire, circuit No. 1082) and harness side of RCM connector C310A, terminal No. 1 (Gray/Orange wire). Measure resistance between harness side of RCM connector C310B, terminal No. 5 (Yellow/Black wire) and harness side of RCM connector C310A, terminal No. 2 (Gray/White wire). Measure resistance between harness side of RCM connector C310B, terminal No. 6 (Yellow/Red wire) and harness side of RCM connector C310A, terminal No. 3 (Light Blue/Orange wire, circuit No. 607). Measure resistance between harness side of RCM connector C310B, terminal No. 6 (Yellow/Red wire) and harness side of RCM connector C310A, terminal No. 4 (Pink/Black wire, circuit No. 616). Measure resistance between harness side of RCM connector C310B, terminal No. 5 (Yellow/Black wire) and harness side of RCM connector C310A, terminal No. 3 (Light Blue/Orange wire). Measure resistance between harness side of RCM connector C310B, terminal No. 5 (Yellow/Black wire) and harness side of RCM connector C310A, terminal No. 4 (Pink/Black wire). If resistance is more than 10 k/ohms in all circuits, go to next step. If resistance is less that 10 k/ohms in any circuit, repair short between appropriate wires. See WIRING DIAGRAMS  . Go to step  8 .
    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.

  6. Confirm RCM fault

    Turn ignition switch to OFF position. Reconnect RCM connectors C310A and C310B. Reconnect air bag simulators to driver- and passenger-side air bag module harness connector. Reconnect right and left seat belt pretensioner harness connectors. Turn ignition switch to ON position. Perform on-demand self-test. If DTC B2792 was retrieved during on-demand self-test, replace RCM. Go to step  8 . If DTC B2297 was not retrieved during on-demand self-test, fault is intermittent. Attempt to recreate fault by flexing wire harness and cycling ignition frequently. See WIRING DIAGRAMS  . Activate other systems in same wire harness. Repair any intermittent problems found. Go to step  8 .

  7. Check for intermittent fault condition

    Clear all DTCs. See CLEARING FAULT CODES  under DIAGNOSTICS. Cycle ignition switch to OFF position and then to ON position. Retrieve and record any continuous DTCs. If DTC B2792 was retrieved, go to step  1 . If DTC B2297 was not retrieved, fault is intermittent. Attempt to recreate fault by flexing wire harness and cycling ignition frequently. See WIRING DIAGRAMS  . Activate other systems in same wire harness. Repair any intermittent problems found. Go to next step.

  8. Check for additional DTCs

    Clear all DTCs. See CLEARING FAULT CODES  under DIAGNOSTICS. Cycle ignition switch to OFF position and then to ON position. Retrieve and record any continuous DTCs. If any continuous DTCs were retrieved, go to diagnostic trouble code identification table for direction to appropriate test. See DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION  table. DO NOT clear any DTCs until all DTCs have been resolved. If no continuous 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.
scientia non olet · About LEMON Manuals