B1784 – OBD-II DTC

OBD-II DTC B1784 – Mirror Passenger Up Circuit Short To Battery

DTC B1784 meaning

DTC B1784 refers to a diagnostic trouble code indicating a fault in the passenger side mirror’s “up” circuit. This code is triggered when the vehicle’s onboard diagnostic system detects a short circuit to battery voltage in the wiring or components associated with the passenger side mirror’s upward movement. Essentially, it means that the system has identified an electrical issue that prevents the mirror from functioning correctly in the upward direction.

DTC B1784 symptoms

Common symptoms associated with DTC B1784 may include:

• The passenger side mirror does not move up when the control switch is activated.
• Intermittent or erratic movement of the passenger side mirror.
• Other mirror functions (left, right, down) may still operate normally.
• Dashboard warning lights may illuminate, indicating a fault in the mirror system.

DTC B1784 causes

Several potential causes for DTC B1784 include:

• A short circuit in the wiring harness leading to the passenger side mirror.
• Faulty mirror switch or control module.
• Corroded or damaged connectors in the mirror circuit.
• Defective mirror motor that may be drawing excessive current.

DTC B1784 seriousness

The seriousness of DTC B1784 can vary based on the vehicle’s use and the driver’s reliance on the passenger side mirror. While it may not pose an immediate safety risk, it can hinder visibility and increase the likelihood of accidents. Therefore, it is advisable to address this issue promptly to ensure all mirror functions operate correctly.

How to diagnose DTC B1784

To diagnose DTC B1784, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the B1784 code.
2. Inspect the wiring and connectors leading to the passenger side mirror for any visible damage or corrosion.
3. Test the mirror switch for proper operation using a multimeter.
4. Check for continuity in the wiring harness to ensure there are no breaks or shorts.
5. Examine the mirror motor for any signs of malfunction or excessive current draw.

How to fix DTC B1784 step-by-step instructions

To fix DTC B1784, follow these step-by-step instructions:

1. Disconnect the vehicle’s battery to ensure safety while working on the electrical system.
2. Inspect and repair any damaged wiring or connectors found during the diagnosis.
3. If the mirror switch is faulty, replace it with a new one.
4. Replace the mirror motor if it is determined to be defective.
5. Reconnect the battery and clear the DTC using an OBD-II scanner.
6. Test the passenger side mirror to ensure it operates correctly in all directions.

How to erase DTC B1784

To erase DTC B1784, 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 from the vehicle’s memory.
5. Disconnect the scanner and start the vehicle to ensure the code does not reappear.

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