Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer has detected a problem with the part that checks for leaks in the fuel tank. It's like a sensor that helps make sure no gasoline is leaking out, and it's not working right.
The P1431 code indicates that there is an issue with the heater control circuit of the Diagnostic Module Tank Leakage (DM TL) system, which is responsible for detecting leaks in the fuel system.
The DM TL system uses a heater to ensure proper operation of the leak detection pump. This code is triggered when the control circuit for this heater shows a high voltage condition, indicating a potential fault in the circuit or the heater itself.
• Check Engine Light (CEL) is on
• Failed emissions test
• Possible fuel smell from the vehicle
• Faulty DM TL heater
• Open or shorted wiring in the DM TL heater circuit
• Faulty ECM (Engine Control Module)
DM TL: Diagnostic Module Tank Leakage
ECM: Engine Control Module
• Scan the vehicle for codes and freeze frame data
• Inspect the wiring and connectors for the DM TL heater
• Test the DM TL heater for proper operation and resistance
• Repair or replace damaged wiring or connectors
• Replace the DM TL heater
• Replace or reprogram the ECM if necessary
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• BMW 3 Series
• BMW 5 Series
• BMW X5
• Regularly inspect and maintain the fuel system
• Ensure all vehicle recalls are addressed
• Use high-quality fuel to prevent deposits
Sensor Issue
• Have the vehicle inspected by a professional
• Avoid driving the vehicle until the issue is resolved to prevent further damage
Check if the vehicle is still under warranty for emissions-related components.
This code has been more common in vehicles with higher mileage and those that have not had regular maintenance.
Moderate – Should be addressed to avoid potential emissions issues and ensure vehicle safety.
Driving with a fuel system leak can be hazardous and may violate emissions regulations.
• Engine must be off
• Vehicle on a level surface
The DM TL heater is typically located near the fuel tank or in the rear of the vehicle.
Q: Can I drive with a P1431 code?
A: It's not recommended to drive with this code as it may indicate a fuel system leak, which can be dangerous.
Q: How do I clear a P1431 code?
A: After repairs, use an OBD-II scanner to clear the code. However, ensure the issue is fixed to prevent it from returning.
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