Fuel Level Sending Unit Failure

Monitored & Set Condition

1. When Monitored: With the ignition on.
2. Set Condition: The BCM detects excessive voltage on the fuel level sensor signal circuit.

Possible Causes:

• Fuel Pump Module
• Ground Circuit Open
• Measure The Fuel Level Sensor Signal Circuit
• Open Fuel Level Sensor Signal Circuit
• Body Control Module

Testing

1. Turn ignition off. Remove rear seat cushion. Disconnect C308 Black connector. Turn ignition on. Measure voltage on C308 Black connector terminal No. 3, fuel level sensor signal circuit (Dark Blue wire). See Figure . If voltage is more than 10 volts, leave C308 Black connector disconnected and go to next step. If voltage is 10 volts or less, go to step  5 .
2. Connect a 12-volt test light between ground and C308 Black connector terminal No. 3, fuel level sensor signal circuit (Dark Blue wire). If test light illuminates, leave C308 Black connector disconnected and go to next step. If test light does not illuminate, leave C308 Black connector disconnected and go to step  4 .
3. Turn ignition off. Disconnect Body Control Module (BCM) connector C4. Turn ignition on. Connect a 12-volt test light between ground and C308 Black connector terminal No. 3, fuel level sensor signal circuit (Dark Blue wire). If test light illuminates, repair short to voltage in Dark Blue wire. If test light does not illuminate, replace BCM. See BODY CONTROL MODULE  under REMOVAL & INSTALLATION.
4. Turn ignition off. Measure resistance between ground and C308 Black connector terminal No. 2, ground circuit (Black wire). If resistance is less than 10 ohms, replace fuel pump module. See FUEL PUMP MODULE in REMOVAL, OVERHAUL & INSTALLATION - CONCORDE, INTREPID & 300M article in ENGINE PERFORMANCE. If resistance is 10 ohms or more, repair open in Black wire.
5. Turn ignition off. Ensure C308 Black connector is properly connected. Connect scan tool to Data Link Connector (DLC). Using scan tool, read FUEL LEVEL voltage. If voltage is more than 9 volts, repair open in Dark Blue wire between Body Control Module (BCM) and fuel pump module. If voltage is 9 volts or less, 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.