B1329 – OBD-II DTC

OBD-II DTC B1329 – Passenger Door Ajar Circuit Short To Battery

DTC B1329 meaning

DTC B1329 refers to a diagnostic trouble code indicating a short circuit in the passenger door ajar circuit to battery. This code is generated when the vehicle’s onboard diagnostic system detects that the signal from the passenger door switch is continuously indicating that the door is open, even when it is closed. This can lead to issues with the vehicle’s interior lights, alarm system, and other related functions.

DTC B1329 symptoms

Common symptoms associated with DTC B1329 may include:

• Interior lights remaining on when the vehicle is off
• Door ajar warning light illuminated on the dashboard
• Alarm system malfunctioning or false alarms
• Increased battery drain due to lights staying on

DTC B1329 causes

Several factors can lead to the triggering of DTC B1329, including:

• Faulty passenger door switch
• Wiring issues, such as frayed or shorted wires
• Corrosion in the door connector or terminals
• Faulty body control module (BCM)

DTC B1329 seriousness

DTC B1329 is considered a moderate issue. While it may not affect the vehicle’s drivability, it can lead to battery drain and inconvenience due to malfunctioning interior lights and alarm systems. If left unaddressed, it may result in a dead battery or further electrical issues.

How to diagnose DTC B1329

To diagnose DTC B1329, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the B1329 code.
2. Inspect the passenger door switch for proper operation.
3. Check the wiring and connectors for any signs of damage or corrosion.
4. Test the continuity of the circuit from the switch to the BCM.
5. Examine the BCM for any faults or error codes.

How to fix DTC B1329 step-by-step instructions

To fix DTC B1329, follow these steps:

1. Inspect and replace the passenger door switch if it is faulty.
2. Repair or replace any damaged wiring or connectors.
3. Clean any corrosion found in the door connector or terminals.
4. If necessary, reprogram or replace the body control module.
5. Clear the DTC using an OBD-II scanner and test the system to ensure the issue is resolved.

How to erase DTC B1329

To erase DTC B1329, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn the ignition key to the “On” position without starting the engine.
3. Navigate to the “Erase Codes” or “Clear DTCs” option on the scanner.
4. Confirm the action to clear the trouble codes.
5. Disconnect the scanner and start the vehicle to check if the code returns.

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