Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the part of the car that checks if the gas tank is leaking. It's like a heater that helps the car test for leaks, and it's not working right now.
The Diagnostic Module Tank Leakage (DM TL) is responsible for checking the fuel system for leaks. The heater in this module helps the system perform accurate tests, and an open circuit means there's a break in the electrical path.
The P1429 code indicates that the heater control circuit for the Diagnostic Module Tank Leakage (DM TL) is open. This means there is a disruption in the electrical circuit that powers the heater, which is crucial for the module's operation in leak detection.
• Check Engine Light is on
• Failed emissions test
• Possible fuel odor
• Faulty DM TL heater
• Damaged wiring or connectors
• Blown fuse
DM TL: Diagnostic Module Tank Leakage
Heater Control Circuit: The electrical circuit responsible for powering the heater in the DM TL system
• Check the wiring and connectors for damage.
• Test the DM TL heater for continuity.
• Inspect and replace any blown fuses.
• Repair or replace damaged wiring or connectors.
• Replace the DM TL heater if faulty.
• Replace any blown fuses.
• Multimeter
• OBD-II scanner
• Basic hand tools
$100 - $300
Moderate
• BMW 3 Series
• BMW 5 Series
• BMW X5
• Regularly inspect fuel system components.
• Ensure proper electrical connections.
• Perform routine maintenance checks.
Sensor Issue
• Do not ignore the Check Engine Light.
• Get the vehicle inspected by a professional.
• Avoid DIY repairs unless experienced.
Check vehicle warranty for coverage on emissions-related components.
This code is commonly associated with BMW vehicles and often arises due to electrical issues in the DM TL system.
Moderate – Addressing this issue is important to ensure the vehicle passes emissions tests and operates efficiently.
Driving with a malfunctioning emissions system can lead to fines and environmental harm.
• Vehicle must be at operating temperature.
• Ensure fuel tank is not overfilled.
The DM TL is typically located near the fuel tank or in the rear of the vehicle.
Q: Can I drive with a P1429 code?
A: While the car may still drive, it's important to fix this issue to avoid emissions problems and potential fines.
Q: Will a P1429 code affect my car's performance?
A: It may not directly affect performance, but it can lead to emissions test failures and potential fuel system issues.
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