B1748 – OBD-II DTC

OBD-II DTC B1748 – Mirror Passenger Horizontal Switch Circuit Short To Ground

DTC B1748 meaning

DTC B1748 refers to a diagnostic trouble code indicating a short circuit to ground in the passenger side mirror horizontal switch circuit. This code is part of the On-Board Diagnostics II (OBD-II) system, which monitors various vehicle systems for faults. The horizontal switch is responsible for controlling the left and right movement of the passenger side mirror.

DTC B1748 symptoms

Common symptoms associated with DTC B1748 may include:

• Inability to adjust the passenger side mirror horizontally.
• Passenger side 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, potentially affecting other components.

DTC B1748 causes

Several factors can lead to the occurrence of DTC B1748, including:

• Faulty horizontal switch in the passenger side mirror.
• Wiring issues, such as frayed or damaged wires.
• Corrosion or poor connections in the electrical circuit.
• Short circuit in the wiring harness.
• Faulty body control module (BCM) or mirror control module.

DTC B1748 seriousness

The seriousness of DTC B1748 can vary. While it may not pose an immediate safety risk, it can lead to:

• Inability to adjust the passenger side mirror, affecting visibility.
• Potential for further electrical issues if not addressed.
• Increased difficulty in passing vehicle inspections if applicable.

How to diagnose DTC B1748

To diagnose DTC B1748, follow these steps:

• Use an OBD-II scanner to confirm the presence of the code.
• Inspect the wiring and connectors related to the passenger side mirror switch for damage or corrosion.
• Test the horizontal switch for proper operation using a multimeter.
• Check for any additional codes that may indicate related issues.
• Examine the body control module for faults or updates.

How to fix DTC B1748 step-by-step instructions

To fix DTC B1748, follow these step-by-step instructions:

1. Disconnect the vehicle’s battery to ensure safety.
2. Inspect the wiring harness and connectors for any visible damage or corrosion.
3. If damage is found, repair or replace the affected wiring or connectors.
4. Test the horizontal switch using a multimeter to ensure it is functioning correctly.
5. If the switch is faulty, replace it with a new one.
6. Reconnect the battery and clear the DTC using an OBD-II scanner.
7. Test the passenger side mirror to ensure it operates correctly.

How to erase DTC B1748

To erase DTC B1748, follow these steps:

• Connect an OBD-II scanner to the vehicle’s diagnostic port.
• Turn on the ignition without starting the engine.
• Navigate to the option to clear or erase trouble codes on the scanner.
• Confirm the action to erase the codes.
• Disconnect the scanner and start the vehicle to check if the code returns.

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