B1643 – OBD-II DTC

OBD-II DTC B1643 – Mirror Passenger Right Circuit Failure

DTC B1643 meaning

DTC B1643 refers to a diagnostic trouble code indicating a failure in the passenger side mirror circuit. This code is part of the On-Board Diagnostics II (OBD-II) system, which monitors various vehicle components for faults. Specifically, B1643 points to an issue with the electrical circuit that controls the right-side mirror, which may affect its functionality, including adjustments and heating features.

DTC B1643 symptoms

Common symptoms associated with DTC B1643 may include:

• The passenger side mirror not adjusting properly.
• Inability to heat the passenger side mirror if equipped.
• Warning lights or messages on the dashboard related to the mirror system.
• Intermittent or complete failure of the mirror’s electrical functions.

DTC B1643 causes

Several factors can lead to the triggering of DTC B1643, including:

• Faulty wiring or connectors in the mirror circuit.
• Defective mirror motor or control module.
• Corrosion or damage to the electrical connections.
• Issues with the vehicle’s body control module (BCM).
• Blown fuses related to the mirror circuit.

DTC B1643 seriousness

The seriousness of DTC B1643 can vary. While it may not pose an immediate safety risk, it can affect the driver’s visibility and comfort. If the passenger side mirror is not functioning correctly, it can lead to unsafe driving conditions. Therefore, it is advisable to address this issue promptly to ensure all vehicle components are operating as intended.

How to diagnose DTC B1643

To diagnose DTC B1643, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the B1643 code.
2. Inspect the passenger side mirror and its wiring for visible damage or disconnections.
3. Check the fuses related to the mirror circuit for any blown fuses.
4. Test the mirror motor and control module for proper operation.
5. Examine the body control module (BCM) for any faults or issues.

How to fix DTC B1643 step-by-step instructions

To fix DTC B1643, follow these step-by-step instructions:

1. Start by disconnecting the vehicle’s battery to ensure safety.
2. Inspect the wiring and connectors leading to the passenger side mirror for any signs of damage or corrosion.
3. Replace any damaged wiring or connectors as necessary.
4. Check and replace any blown fuses related to the mirror circuit.
5. Test the mirror motor and control module replace them if they are found to be defective.
6. Reconnect the battery and clear the DTC using an OBD-II scanner.
7. Test the passenger side mirror to ensure it operates correctly.

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