B1747: Mirror Passenger Horizontal Switch Circuit Short To Battery

Definition

The OBD2 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

Common causes

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 misdiagnoses

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

Troubleshooting steps

1. 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
2. Inspect the Wiring and Connectors
3. Check the wiring harness and connectors associated with the passenger side mirror switch. Look for any signs of damage, fraying, or corrosion
4. Ensure that all connectors are securely attached and free of dirt or moisture
5. Check the Switch
6. 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
7. If the switch is faulty, it may need to be replaced
8. Inspect the Mirror Assembly
9. Check the passenger side mirror assembly for any signs of damage or short circuits. Sometimes, the mirror motor or internal wiring can cause issues
10. If the mirror assembly is damaged, it may need to be repaired or replaced
11. Test for Short Circuits
12. Use a multimeter to check for shorts in the wiring. Disconnect the switch and check the resistance between the switch terminals and ground
13. If you find a short, trace the wiring back to locate the source of the short
14. Check for Ground Issues
15. Ensure that the ground connections for the mirror switch and motor are secure and free of corrosion. A poor ground can cause erratic behavior
16. Inspect Related Components
17. 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
18. Consult Wiring Diagrams
19. Refer to the vehicle’s wiring diagrams to understand the circuit better and identify any other components that may be involved
20. Perform a System Reset
21. After repairs, clear the code and perform a system reset. Monitor the system to see if the code returns
22. Seek Professional Help
23. 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

Definition

Common causes

Common misdiagnoses

Troubleshooting steps

1. Verify the Code

2. Inspect the Wiring and Connectors

3. Check the wiring harness and connectors associated with the passenger side mirror switch. Look for any signs of damage, fraying, or corrosion

4. Ensure that all connectors are securely attached and free of dirt or moisture

5. Check the Switch

6. 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

7. If the switch is faulty, it may need to be replaced

8. Inspect the Mirror Assembly

9. Check the passenger side mirror assembly for any signs of damage or short circuits. Sometimes, the mirror motor or internal wiring can cause issues

10. If the mirror assembly is damaged, it may need to be repaired or replaced

11. Test for Short Circuits

12. Use a multimeter to check for shorts in the wiring. Disconnect the switch and check the resistance between the switch terminals and ground

13. If you find a short, trace the wiring back to locate the source of the short

14. Check for Ground Issues

15. Ensure that the ground connections for the mirror switch and motor are secure and free of corrosion. A poor ground can cause erratic behavior

16. Inspect Related Components

17. 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

18. Consult Wiring Diagrams

19. Refer to the vehicle’s wiring diagrams to understand the circuit better and identify any other components that may be involved

20. Perform a System Reset

21. After repairs, clear the code and perform a system reset. Monitor the system to see if the code returns

22. Seek Professional Help

23. 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