U1131 – Lost Communication with Fuel Level Sensor.

The ODBII code U1131 indicates that there is a loss of communication between the vehicle’s control module and the fuel level sensor, which may affect the accurate reading of the fuel level.

The severity of ODBII code U1131 is generally considered moderate.

Common Causes For: U1130 SCP (J1850) Invalid or Missing Data for Fuel System

• Faulty fuel level sensor
• Damaged wiring or connectors
• Poor ground connection
• Failed fuel pump module
• Malfunctioning engine control module (ECM)
• Corroded or loose electrical connections
• Software issues or glitches in the vehicle’s computer system

Common misdiagnosis for U1131 Lost Communication with Fuel Level Sensor.

• Faulty fuel level sensor
• Wiring issues or shorts in the harness
• Bad fuel gauge
• Faulty engine control module (ECM)
• Corroded connectors
• Instrument cluster malfunction
• Grounding issues
• Fuel tank issues (e.g., damage or leaks)

Common Troubleshooting Steps

When dealing with the OBD-II code U1131, which indicates “Lost Communication with Fuel Level Sensor,” there are several common troubleshooting steps you can take to diagnose and potentially resolve the issue. Here’s a structured approach:

• Check for Additional Codes: Use an OBD-II scanner to check for any other trouble codes that may be present. This can provide more context and help identify related issues.
• Inspect the Fuel Level Sensor: **Location: Locate the fuel level sensor, which is typically found in the fuel tank.
• **Visual Inspection: Check for any visible damage to the sensor or its wiring. Look for frayed wires, corrosion, or loose connections.
• Check Electrical Connections: **Connector Inspection: Ensure that the electrical connectors to the fuel level sensor are secure and free of corrosion or dirt.
• **Wiring: Inspect the wiring harness for any signs of wear, damage, or shorts. Pay special attention to areas where the wiring may be exposed to heat or moving parts.
• Test the Fuel Level Sensor: **Resistance Test: Use a multimeter to measure the resistance of the fuel level sensor. Compare the readings to the specifications provided in the vehicle’s service manual.
• **Functionality Test: If possible, test the sensor by applying a known voltage and checking the output signal.
• Check the Fuel Pump Module: In some vehicles, the fuel level sensor is part of the fuel pump module. Ensure that the entire module is functioning correctly.
• Inspect the Instrument Cluster: If the fuel level sensor is functioning correctly, the issue may lie within the instrument cluster. Check for any faults in the cluster that could affect communication.
• Check for Ground Issues: Ensure that the ground connections for the fuel level sensor and related components are secure and free of corrosion.
• Scan for Communication Issues: Use a scan tool to check for communication between the fuel level sensor and the vehicle’s computer. Look for any communication errors that may indicate a problem with the CAN bus or other communication lines.
• Check for Software Updates: Sometimes, manufacturers release software updates that can resolve communication issues. Check if there are any updates available for your vehicle’s ECU.
• Clear Codes and Test Drive: After performing the above checks and repairs, clear the trouble codes using the OBD-II scanner and take the vehicle for a test drive to see if the code returns.1
• Consult a Professional: If the issue persists after performing these steps, it may be necessary to consult a professional mechanic or technician who has access to specialized diagnostic equipment. By following these troubleshooting steps, you should be able to identify and resolve the issue related to the U1131 code. Always refer to the specific service manual for your vehicle for detailed procedures and specifications.