B1742: Mirror Passenger Vertical Switch Circuit Open

Definition

The OBD2 code B1742 indicates an open circuit in the passenger side mirror's vertical switch, meaning there is a malfunction preventing the switch from functioning properly

Common causes

Faulty passenger mirror vertical switch
Open circuit in the wiring harness
Corroded or damaged connectors
Faulty body control module (BCM)
Blown fuse related to the mirror system
Ground connection issues

Common misdiagnoses

Faulty passenger side mirror motor
Wiring issues or shorts in the mirror circuit
Defective mirror switch assembly
Body control module (BCM) malfunction
Incorrectly diagnosed window switch problems
Issues with the vehicle's electrical system or grounds
Faulty connectors or terminals related to the mirror circuit

Troubleshooting steps

1. Check for Additional Codes

Use an OBD-II scanner to check for any other related trouble codes that may provide more context or indicate other issues
2. Inspect the Wiring and Connectors
3. Visually inspect the wiring harness and connectors associated with the passenger side mirror. Look for any signs of damage, fraying, corrosion, or loose connections
4. Pay special attention to the wiring that runs through the door, as this area is prone to wear and tear
5. Test the Switch
6. Remove the switch from the door panel and test it with a multimeter. Check for continuity when the switch is activated. If the switch is faulty, it may need to be replaced
7. Check the Mirror Motor
8. If the switch tests good, the issue may lie with the mirror motor itself. Test the motor for proper operation by applying direct power to it (if safe to do so) to see if it responds
9. Inspect the Ground Connection
10. Ensure that the ground connection for the mirror and switch is secure and free of corrosion. A poor ground can cause circuit issues
11. Check for Short Circuits
12. Use a multimeter to check for any short circuits in the wiring. This can help identify if there is a short to ground or another wire
13. Look for Water Intrusion
14. Check for any signs of water intrusion in the door or around the mirror assembly, as moisture can cause electrical issues
15. Consult Wiring Diagrams
16. Refer to the vehicle’s wiring diagrams to understand the circuit layout and identify any other components that may be involved in the circuit
17. Perform a System Reset
18. After addressing any issues found, clear the trouble codes using the OBD-II scanner and see if the code returns after a test drive
19. Seek Professional Help
20. If the issue persists after performing these steps, it may be necessary to consult a professional mechanic or an automotive electrician for further diagnosis. By following these steps, you should be able to identify and resolve the issue related to the B1742 code

Definition

Common causes

Common misdiagnoses

Troubleshooting steps

1. Check for Additional Codes

2. Inspect the Wiring and Connectors

3. Visually inspect the wiring harness and connectors associated with the passenger side mirror. Look for any signs of damage, fraying, corrosion, or loose connections

4. Pay special attention to the wiring that runs through the door, as this area is prone to wear and tear

5. Test the Switch

6. Remove the switch from the door panel and test it with a multimeter. Check for continuity when the switch is activated. If the switch is faulty, it may need to be replaced

7. Check the Mirror Motor

8. If the switch tests good, the issue may lie with the mirror motor itself. Test the motor for proper operation by applying direct power to it (if safe to do so) to see if it responds

9. Inspect the Ground Connection

10. Ensure that the ground connection for the mirror and switch is secure and free of corrosion. A poor ground can cause circuit issues

11. Check for Short Circuits

12. Use a multimeter to check for any short circuits in the wiring. This can help identify if there is a short to ground or another wire

13. Look for Water Intrusion

14. Check for any signs of water intrusion in the door or around the mirror assembly, as moisture can cause electrical issues

15. Consult Wiring Diagrams

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

17. Perform a System Reset

18. After addressing any issues found, clear the trouble codes using the OBD-II scanner and see if the code returns after a test drive

19. Seek Professional Help

20. If the issue persists after performing these steps, it may be necessary to consult a professional mechanic or an automotive electrician for further diagnosis. By following these steps, you should be able to identify and resolve the issue related to the B1742 code