Seat Belt Indicator Not Operating Properly

Possible Causes:

• Body Control Module (Seat Belt Switch Sense Circuit Shorted To Ground)
• Check The Seat Belt Switch Status
• Perform Instrument Cluster Self Test
• Seat Belt Switch Sense Circuit Shorted To Ground
• Seat Belt Switch Shorted To Ground
• Wiring Harness Intermittent Defect
• Body Control Module (Open Seat Belt Switch Sense Circuit)
• Check The Seat Belt Switch Status
• Open Ground Circuit
• Open Seat Belt Switch
• Seat Belt Switch Sense Circuit Open

Testing

1. To start bulb test, turn ignition off, then on. If seat belt indicator illuminates, go to next step. If seat belt indicator does not illuminate, replace instrument cluster. See ANALOG INSTRUMENT PANELS - CONCORDE, INTREPID & 300M article.
2. Turn ignition off. Buckle driver seat belt. Turn ignition on. If seat belt indicator goes out, go to next step. If seat belt indicator does not go out, go to step  8 .
3. Unbuckle driver seat belt. If seat belt indicator does not illuminate, go to next step. If seat belt indicator illuminates, fault may be intermittent. Check related wiring and connectors for poor connections or damage to wiring harness. See WIRING DIAGRAMS  . Repair any problems found as necessary. If no problems are found, check if any Technical Service Bulletins (TSBs) apply to vehicle. If no TSBs apply, test is complete.
4. Turn ignition off. Ensure driver seat belt is unbuckled. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Using scan tool, read SEAT BELT SWITCH status. If scan tool displays CLOSED, replace instrument cluster. See ANALOG INSTRUMENT PANELS - CONCORDE, INTREPID & 300M article. If scan tool displays OPEN, go to next step.
5. Turn ignition off. Disconnect 2-pin seat belt switch connector. Measure resistance between ground and seat belt switch connector terminal No.2, ground circuit (Black/Light Green wire). If resistance is less than 5 ohms, leave seat belt switch connector disconnected and go to next step. If resistance is 5 ohms or more, repair open in Black/Light Green wire.
6. Connect a fused jumper wire between seat belt switch connector terminal No. 1, seat belt switch sense circuit (Light Green/Red wire) and No. 2, ground circuit (Black/Light Green wire). Using scan tool, read SEAT BELT SWITCH status. If scan tool displays CLOSED, replace seat belt switch. If scan tool displays OPEN, leave seat belt switch connector disconnected and go to next step.
7. Ensure ignition is off. Disconnect Body Control Module (BCM) connector C4. Measure resistance in seat belt switch sense circuit (Light Green/Red wire) between BCM connector C4 terminal No. 15 and seat belt switch connector terminal No. 1. See Figure . If resistance is less than 5 ohms, replace BCM. See BODY CONTROL MODULE  under REMOVAL & INSTALLATION. If resistance is 5 ohms or more, repair open in Light Green/Red wire.
8. Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Buckle driver seat belt. Using scan tool, read SEAT BELT SWITCH status. If scan tool displays OPEN, replace instrument cluster. See ANALOG INSTRUMENT PANELS - CONCORDE, INTREPID & 300M article. If scan tool does not display OPEN, go to next step.
9. Disconnect seat belt switch connector. Using scan tool, read SEAT BELT SWITCH status. If scan tool displays OPEN is displayed, replace seat belt switch. If scan tool does not display OPEN, leave seat belt switch connector disconnected and go to next step.
10. Turn ignition off. Disconnect Body Control Module (BCM) connector C4. Measure resistance between ground and BCM connector C4, terminal No. 15, seat belt switch sense circuit (Light Green/Red wire). See Figure . If resistance is less than 100 ohms, repair short to ground in Light Green/Red wire. If resistance is 100 ohms or more, replace BCM. See BODY CONTROL MODULE  under REMOVAL & INSTALLATION.