B1747 – Mirror Passenger Horizontal Switch Circuit Short To Battery

The ODBII code B1747 indicates a short circuit in the passenger side mirror’s horizontal switch circuit, causing it to be connected directly to the battery voltage.

The severity of ODBII code B1747 is moderate.

Common Causes For: B1746 Mirror Passenger Horizontal Switch Circuit Open

• Shorted wiring or connectors
• Faulty passenger mirror switch
• Damaged or corroded electrical connections
• Malfunctioning body control module (BCM)
• Grounding issues
• Water intrusion or moisture damage

Common misdiagnosis for B1747 Mirror Passenger Horizontal Switch Circuit Short To Battery

• Faulty passenger side mirror switch
• Wiring issues in the mirror circuit
• Faulty body control module (BCM)
• Short circuit in the wiring harness
• Defective passenger side mirror motor
• Issues with the vehicle’s electrical system
• Faulty connectors or terminals in the mirror circuit

Common Troubleshooting Steps

When dealing with an OBD-II code B1747, which indicates a “Mirror Passenger Horizontal Switch Circuit Short To Battery,” you can follow these common troubleshooting steps:

• Verify the Code: Use an OBD-II scanner to confirm the presence of the B1747 code. Clear the code and see if it returns after a short drive.
• Inspect the Wiring and Connectors:
• Check the wiring harness and connectors associated with the passenger side mirror switch. Look for any signs of damage, fraying, or corrosion.
• Ensure that all connectors are securely attached and free of dirt or moisture.
• Check the Switch:
• Test the passenger mirror switch for proper operation. You can do this by using a multimeter to check for continuity and resistance in the switch.
• If the switch is faulty, it may need to be replaced.
• Inspect the Mirror Assembly:
• Check the passenger side mirror assembly for any signs of damage or short circuits. Sometimes, the mirror motor or internal wiring can cause issues.
• If the mirror assembly is damaged, it may need to be repaired or replaced.
• Test for Short Circuits:
• Use a multimeter to check for shorts in the wiring. Disconnect the switch and check the resistance between the switch terminals and ground.
• If you find a short, trace the wiring back to locate the source of the short.
• Check for Ground Issues:
• Ensure that the ground connections for the mirror switch and motor are secure and free of corrosion. A poor ground can cause erratic behavior.
• Inspect Related Components:
• Check any related components, such as the body control module (BCM) or any fuses associated with the mirror circuit. A malfunctioning BCM can sometimes cause issues with the mirror controls.
• Consult Wiring Diagrams:
• Refer to the vehicle’s wiring diagrams to understand the circuit better and identify any other components that may be involved.
• Perform a System Reset:
• After repairs, clear the code and perform a system reset. Monitor the system to see if the code returns.
• Seek Professional Help:
• If you are unable to resolve the issue after these steps, consider seeking help from a professional mechanic or automotive technician who has experience with electrical systems. By following these steps, you should be able to diagnose and potentially fix the issue related to the B1747 code.