B1782 – Mirror Passenger Up Circuit Failure

The ODBII code B1782 indicates a malfunction in the passenger side mirror’s up movement circuit, suggesting a failure in the electrical system or components related to the mirror’s adjustment function.

The severity of ODBII code B1782 is moderate.

Common Causes For: B1781 Mirror Driver Down Short To Ground

• Faulty passenger side mirror switch
• Damaged wiring or connectors in the mirror circuit
• Defective passenger side mirror motor
• Short circuit in the mirror control circuit
• Corroded or loose electrical connections
• Failed body control module (BCM)

Common misdiagnosis for B1782 Mirror Passenger Up Circuit Failure

• Faulty window switch
• Wiring issues or shorts in the harness
• Defective power mirror motor
• Malfunctioning body control module (BCM)
• Incorrectly diagnosed door module
• Battery or charging system problems
• Issues with the vehicle’s electrical system or grounds

Common Troubleshooting Steps

The OBD-II code B1782 indicates a “Mirror Passenger Up Circuit Failure,” which typically relates to issues with the power mirror system on the passenger side of the vehicle. Here are some common troubleshooting steps to diagnose and potentially resolve this issue:

• Check the Owner’s Manual: Refer to the vehicle’s service manual for specific information related to the mirror system and wiring diagrams.
• Inspect the Mirror Switch:
• Test the mirror control switch for proper operation. If the switch is faulty, it may not send the correct signals to the mirror.
• Check for any signs of damage or wear on the switch.
• Examine Wiring and Connectors:
• Inspect the wiring harness and connectors leading to the passenger side mirror for any signs of damage, corrosion, or loose connections.
• Look for frayed wires or broken connectors that could interrupt the circuit.
• Test the Mirror Motor:
• If accessible, test the mirror motor for functionality. You can do this by applying direct power to the motor to see if it operates.
• If the motor does not work when powered directly, it may need to be replaced.
• Check for Ground Issues:
• Ensure that the ground connection for the mirror circuit is secure and free of corrosion. A poor ground can cause circuit failures.
• Scan for Additional Codes:
• Use an OBD-II scanner to check for any additional trouble codes that may provide more context or indicate related issues.
• Inspect the Body Control Module (BCM):
• The BCM controls various electrical functions in the vehicle, including the mirrors. Check for any faults or issues with the BCM.
• If necessary, reprogram or replace the BCM.
• Perform a Visual Inspection:
• Look for any signs of water intrusion or physical damage to the mirror assembly that could affect its operation.
• Clear the Code and Test Drive:
• After performing any repairs or adjustments, clear the trouble code using an OBD-II scanner and take the vehicle for a test drive to see if the code returns.
• Consult a Professional:
• If the issue persists after performing these steps, it may be best to consult a professional mechanic or technician who has experience with electrical systems and OBD-II diagnostics. By following these steps, you should be able to identify and resolve the issue related to the B1782 code.