B1644 – OBD-II DTC

OBD-II DTC B1644 – Mirror Passenger Right Circuit Open

DTC B1644 meaning

DTC B1644 refers to a diagnostic trouble code indicating an issue with the passenger side mirror circuit, specifically that the circuit is open. This means that there is a break in the electrical connection that prevents the mirror from functioning properly. The code is part of the On-Board Diagnostics II (OBD-II) system, which monitors various vehicle components for faults.

DTC B1644 symptoms

Common symptoms associated with DTC B1644 may include:

• The passenger side mirror does not adjust or respond to controls.
• Warning lights may illuminate on the dashboard.
• Other electrical components in the vicinity may also malfunction.

DTC B1644 causes

Several factors can lead to the triggering of DTC B1644, including:

• A broken or damaged wire in the mirror circuit.
• A faulty mirror motor or assembly.
• Corrosion or poor connections in the wiring harness.
• Issues with the vehicle’s body control module (BCM).

DTC B1644 seriousness

The seriousness of DTC B1644 can vary. While it may not affect the vehicle’s overall drivability, it can impact safety and convenience. A non-functioning passenger mirror can hinder visibility, increasing the risk of accidents. Therefore, it is advisable to address this issue promptly.

How to diagnose DTC B1644

To diagnose DTC B1644, follow these steps:

• Use an OBD-II scanner to confirm the presence of the code.
• Inspect the wiring and connectors leading to the passenger side mirror for damage or corrosion.
• Test the mirror motor for functionality using a multimeter.
• Check the body control module for any related fault codes.

How to fix DTC B1644 step-by-step instructions

To fix DTC B1644, follow these step-by-step instructions:

1. Disconnect the vehicle’s battery to ensure safety.
2. Inspect the wiring harness for any visible damage or breaks.
3. If damage is found, repair or replace the affected wires.
4. Check the connectors for corrosion and clean them if necessary.
5. Test the mirror motor with a multimeter to ensure it is functioning correctly.
6. If the motor is faulty, replace the mirror assembly.
7. Reconnect the battery and clear the DTC using an OBD-II scanner.
8. Test the passenger side mirror to ensure it operates correctly.

How to erase DTC B1644

To erase DTC B1644, follow these steps:

• Connect an OBD-II scanner to the vehicle’s diagnostic port.
• Turn on the ignition without starting the engine.
• Navigate to the option to clear or erase trouble codes on the scanner.
• Confirm the action and wait for the scanner to complete the process.
• Disconnect the scanner and start the vehicle to ensure the code does not return.

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