B1746 – OBD-II DTC

OBD-II DTC B1746 – Mirror Passenger Horizontal Switch Circuit Open

DTC B1746 meaning

DTC B1746 refers to a diagnostic trouble code indicating an issue with the passenger side mirror’s horizontal switch circuit. This code is triggered when the vehicle’s onboard diagnostic system detects an open circuit in the switch that controls the horizontal movement of the passenger side mirror. The open circuit can prevent the mirror from adjusting properly, affecting visibility and safety.

DTC B1746 symptoms

Common symptoms associated with DTC B1746 may include:

• Inability to adjust the passenger side mirror horizontally.
• Mirror may be stuck in one position.
• Warning lights on the dashboard related to the mirror or electrical system.
• Other electrical issues in the vehicle, such as malfunctioning switches or controls.

DTC B1746 causes

Several factors can lead to the triggering of DTC B1746, including:

• Faulty horizontal switch in the passenger side mirror.
• Damaged wiring or connectors in the mirror adjustment circuit.
• Corrosion or poor connections at the switch or wiring harness.
• Issues with the body control module (BCM) that manages mirror functions.

DTC B1746 seriousness

The seriousness of DTC B1746 can vary, but it is generally 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 passenger side mirror. This can lead to visibility issues, increasing the risk of accidents. It is advisable to address this code promptly.

How to diagnose DTC B1746

To diagnose DTC B1746, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the B1746 code.
2. Inspect the passenger side mirror switch for physical damage or wear.
3. Check the wiring and connectors for signs of corrosion, fraying, or disconnection.
4. Test the continuity of the switch circuit using a multimeter.
5. Examine the body control module for any faults or error codes.

How to fix DTC B1746 step-by-step instructions

To fix DTC B1746, follow these step-by-step instructions:

1. Disconnect the vehicle’s battery to ensure safety while working on electrical components.
2. Remove the passenger side mirror switch from the door panel.
3. Inspect the switch for damage and replace it if necessary.
4. Check the wiring harness for any signs of damage or corrosion and repair or replace as needed.
5. Reconnect all connectors securely and ensure there are no loose connections.
6. Reinstall the switch and reconnect the battery.
7. Use the OBD-II scanner to clear the DTC and test the mirror adjustment functionality.

How to erase DTC B1746

To erase DTC B1746, 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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