B1402 – OBD-II DTC

OBD-II DTC B1402 – Driver Power Window Down Switch Circuit Failure

DTC B1402 meaning

DTC B1402 refers to a fault in the Driver Power Window Down Switch Circuit. This diagnostic trouble code indicates that the vehicle’s onboard diagnostic system has detected an issue with the electrical circuit responsible for the operation of the driver’s side power window down switch. The code is part of the OBD-II system, which monitors various vehicle components for proper functionality.

DTC B1402 symptoms

Common symptoms associated with DTC B1402 may include:

• Power window not functioning properly
• Driver’s side window may not go down
• Intermittent operation of the power window
• Other electrical issues in the driver’s door

DTC B1402 causes

Several factors can lead to the triggering of DTC B1402, including:

• Faulty power window switch
• Wiring issues, such as shorts or open circuits
• Defective power window motor
• Corroded or loose electrical connections
• Faulty body control module (BCM)

DTC B1402 seriousness

The seriousness of DTC B1402 can vary. While it may not pose an immediate safety risk, it can lead to inconvenience due to the inability to operate the driver’s side window. Additionally, if left unaddressed, it may indicate underlying electrical issues that could affect other systems in the vehicle.

How to diagnose DTC B1402

To diagnose DTC B1402, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the code.
2. Inspect the power window switch for physical damage or wear.
3. Check the wiring and connectors for signs of corrosion or damage.
4. Test the power window motor for functionality.
5. Examine the body control module for faults.
6. Perform continuity tests on the circuit to identify any breaks or shorts.

How to fix DTC B1402 step-by-step instructions

To fix DTC B1402, follow these steps:

1. Replace the faulty power window switch if damaged.
2. Repair or replace any damaged wiring or connectors.
3. Replace the power window motor if it is not functioning.
4. Address any issues found with the body control module.
5. Clear the DTC using an OBD-II scanner and test the system.
6. Verify that the power window operates correctly after repairs.

How to erase DTC B1402

To erase DTC B1402, 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. Access the diagnostic trouble codes menu on the scanner.
4. Select the option to clear or erase codes.
5. Confirm the action and wait for the scanner to complete the process.
6. Disconnect the scanner and start the vehicle to ensure the code does not return.

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