B1404 – OBD-II DTC

OBD-II DTC B1404 – Driver Power Window Down Circuit Open

DTC B1404 meaning

DTC B1404 refers to a diagnostic trouble code indicating an open circuit in the driver power window down circuit. This code is part of the On-Board Diagnostics II (OBD-II) system, which monitors various vehicle components and systems for faults. When the power window system detects that the circuit responsible for lowering the driver’s side window is open or interrupted, it triggers this code.

DTC B1404 symptoms

Common symptoms associated with DTC B1404 may include:

• Driver’s side power window not functioning properly.
• Window may not lower at all.
• Intermittent operation of the power window.
• Other electrical components in the driver’s door may also be affected.

DTC B1404 causes

Several factors can lead to the triggering of DTC B1404, including:

• Damaged or frayed wiring in the power window circuit.
• Faulty power window switch.
• Defective power window motor.
• Corrosion or poor connections in the wiring harness.
• Issues with the vehicle’s body control module (BCM).

DTC B1404 seriousness

The seriousness of DTC B1404 can vary. While it may not affect the vehicle’s overall drivability, it can lead to inconvenience due to the inability to operate the driver’s side window. In some cases, it may indicate underlying electrical issues that could affect other systems, making it important to address the code promptly.

How to diagnose DTC B1404

To diagnose DTC B1404, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the B1404 code.
2. Inspect the power window switch for any visible damage or wear.
3. Check the wiring and connectors in the power window circuit for signs of damage or corrosion.
4. Test the power window motor for functionality.
5. Examine the body control module for any faults or issues.
6. Perform continuity tests on the circuit to identify any breaks or opens.

How to fix DTC B1404 step-by-step instructions

To fix DTC B1404, follow these steps:

1. Repair or replace any damaged wiring or connectors found during diagnosis.
2. If the power window switch is faulty, replace it with a new one.
3. Replace the power window motor if it is not functioning correctly.
4. Ensure all connections are clean and secure, especially in the wiring harness.
5. If the body control module is faulty, consider reprogramming or replacing it.
6. Clear the DTC using an OBD-II scanner and test the power window operation.

How to erase DTC B1404

To erase DTC B1404, 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 scanner’s menu and select the option to clear or erase trouble codes.
4. Confirm the action and wait for the scanner to complete the process.
5. Disconnect the scanner and start the vehicle to check if the code reappears.

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