B1742 – OBD-II DTC

OBD-II DTC B1742 – Mirror Passenger Vertical Switch Circuit Open

DTC B1742 meaning

DTC B1742 refers to a diagnostic trouble code indicating an issue with the passenger side mirror’s vertical switch circuit. This code is triggered when the onboard diagnostic system detects an open circuit in the switch that controls the vertical movement of the passenger side mirror. The open circuit can prevent the mirror from adjusting properly, affecting visibility and safety.

DTC B1742 symptoms

Common symptoms associated with DTC B1742 may include:

• The passenger side mirror does not adjust vertically.
• Inconsistent or erratic movement of the mirror when attempting to adjust it.
• Other mirror functions may still work, such as horizontal adjustments.
• Warning lights may illuminate on the dashboard, indicating a fault.

DTC B1742 causes

Several factors can lead to the triggering of DTC B1742, including:

• A faulty vertical switch in the passenger side mirror.
• Wiring issues, such as frayed or broken wires in the circuit.
• Corrosion or poor connections in the electrical connectors.
• Faulty body control module (BCM) that fails to communicate properly with the mirror switch.

DTC B1742 seriousness

DTC B1742 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 passenger side mirror. This can lead to reduced visibility and increase the risk of accidents. It is advisable to address this code promptly to ensure safe operation of the vehicle.

How to diagnose DTC B1742

To diagnose DTC B1742, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the B1742 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 vertical switch using a multimeter to ensure it is functioning correctly.
5. Examine the body control module for any faults or communication issues.

How to fix DTC B1742 step-by-step instructions

To fix DTC B1742, 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 any visible damage and replace it if necessary.
4. Check the wiring harness for any breaks or corrosion and repair or replace as needed.
5. Reconnect all connectors securely and ensure there are no loose connections.
6. Reinstall the mirror 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 B1742

To erase DTC B1742, 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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