B1785 – OBD-II DTC

OBD-II DTC B1785 – Mirror Passenger Up Circuit Short To Ground

DTC B1785 meaning

DTC B1785 refers to a diagnostic trouble code indicating a problem with the passenger side mirror’s up circuit. This code is triggered when the vehicle’s onboard diagnostic system detects a short to ground in the circuit responsible for controlling the upward movement of the passenger side mirror. Essentially, it means that there is an electrical fault preventing the mirror from functioning correctly.

DTC B1785 symptoms

Common symptoms associated with DTC B1785 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 work normally.
• Dashboard warning lights may illuminate, indicating a fault in the mirror system.

DTC B1785 causes

Several factors can lead to the triggering of DTC B1785, including:

• A short circuit in the wiring harness connected to the passenger side mirror.
• Faulty mirror switch or control module.
• Corrosion or damage in the electrical connectors.
• Defective passenger side mirror motor.

DTC B1785 seriousness

DTC B1785 is considered a moderate issue. While it may not affect the vehicle’s overall drivability, it can compromise safety by limiting visibility through the passenger side mirror. It is advisable to address this code promptly to ensure all mirror functions operate correctly and to avoid potential accidents.

How to diagnose DTC B1785

To diagnose DTC B1785, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the B1785 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 up circuit wiring to ensure there are no breaks.
5. Examine the passenger side mirror motor for functionality.

How to fix DTC B1785 step-by-step instructions

To fix DTC B1785, 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 found during diagnosis.
3. If the mirror switch is faulty, replace it with a new one.
4. Test the passenger side mirror motor and replace it if it is not functioning correctly.
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 B1785

To erase DTC B1785, 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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