B1782 – OBD-II DTC

OBD-II DTC B1782 – Mirror Passenger Up Circuit Failure

DTC B1782 meaning

DTC B1782 refers to a diagnostic trouble code indicating a failure in the passenger side mirror’s up circuit. This code is part of the On-Board Diagnostics II (OBD-II) system, which monitors various vehicle components and systems for faults. The up circuit specifically controls the movement of the passenger side mirror in the upward direction, and a failure in this circuit can prevent the mirror from adjusting properly.

DTC B1782 symptoms

Common symptoms associated with DTC B1782 may include:

• Passenger side mirror not moving up when the control switch is activated.
• Mirror may be stuck in a fixed position.
• Other mirror functions (left, right, down) may still operate normally.
• Possible warning lights on the dashboard related to the mirror or electrical system.

DTC B1782 causes

Several factors can lead to the occurrence of DTC B1782, including:

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

DTC B1782 seriousness

The seriousness of DTC B1782 can vary based on the vehicle’s use and the driver’s needs. While it may not affect the vehicle’s overall performance, it can impact safety and convenience. A non-adjustable mirror can create blind spots, increasing the risk of accidents. Therefore, it is advisable to address this issue promptly.

How to diagnose DTC B1782

To diagnose DTC B1782, follow these steps:

1. Use an OBD-II scanner to confirm the presence of DTC B1782.
2. Inspect the mirror adjustment switch for any visible damage or wear.
3. Check the wiring and connectors for continuity and signs of damage.
4. Test the mirror motor by applying direct power to see if it operates.
5. Examine the body control module for any fault codes or issues.

How to fix DTC B1782 step-by-step instructions

To fix DTC B1782, follow these step-by-step instructions:

1. Disconnect the vehicle’s battery to ensure safety while working on electrical components.
2. Remove the door panel to access the mirror adjustment switch and wiring.
3. Inspect and repair or replace any damaged wiring or connectors.
4. Test the mirror adjustment switch for functionality and replace if necessary.
5. Check the mirror motor and replace it if it is found to be defective.
6. Reassemble the door panel and reconnect the battery.
7. Clear the DTC using an OBD-II scanner and test the mirror operation.

How to erase DTC B1782

To erase DTC B1782, 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 “Erase Codes” or “Clear DTCs” option on the scanner.
4. Confirm the action to clear the trouble codes.
5. Disconnect the scanner and start the vehicle to ensure the code does not return.

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