B1779 – OBD-II DTC

OBD-II DTC B1779 – Mirror Driver Down Circuit Open

DTC B1779 meaning

DTC B1779 refers to a diagnostic trouble code indicating an issue with the mirror driver down circuit. This code is triggered when the vehicle’s onboard diagnostic system detects an open circuit in the wiring or components responsible for controlling the downward movement of the side mirror. The open circuit can prevent the mirror from adjusting properly, affecting visibility and safety.

DTC B1779 symptoms

Common symptoms associated with DTC B1779 may include:

• Inability to adjust the side mirror downwards
• Mirror adjustment controls may be unresponsive
• Other mirror functions may work, but the downward movement is affected
• Possible warning lights on the dashboard related to the mirror system

DTC B1779 causes

The causes of DTC B1779 can include:

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

DTC B1779 seriousness

DTC B1779 is considered a moderate issue. While it may not immediately affect the vehicle’s drivability, it can compromise safety by limiting the driver’s ability to adjust the side mirror for optimal visibility. It is advisable to address this code promptly to ensure safe driving conditions.

How to diagnose DTC B1779

To diagnose DTC B1779, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the B1779 code.
2. Inspect the mirror adjustment switch for any visible damage or wear.
3. Check the wiring and connectors in the mirror adjustment circuit for signs of damage or corrosion.
4. Test the mirror motor for functionality using a multimeter.
5. Examine the body control module for any related fault codes or issues.

How to fix DTC B1779 step-by-step instructions

To fix DTC B1779, follow these steps:

1. Disconnect the vehicle’s battery to ensure safety while working on electrical components.
2. Inspect and repair any damaged wiring or connectors in the mirror adjustment circuit.
3. Replace the mirror adjustment switch if it is found to be faulty.
4. Test and replace the mirror motor if it is not functioning correctly.
5. Reconnect the battery and clear the DTC using an OBD-II scanner.
6. Test the mirror adjustment functions to ensure proper operation.

How to erase DTC B1779

To erase DTC B1779, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn on the vehicle’s ignition without starting the engine.
3. Navigate to the option to clear or erase trouble codes on the scanner.
4. Confirm the action to erase the DTC.
5. Disconnect the scanner and start the vehicle to ensure the code does not reappear.

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