B1641 – Mirror Passenger Left Circuit Short To Battery

The ODBII code B1641 indicates a short circuit in the passenger side mirror’s left circuit, causing it to connect directly to the battery, which can lead to malfunctioning of the mirror’s electrical components.

The severity of ODBII code B1641 is moderate.

Common Causes For: B1640 Mirror Passenger Left Circuit Open

• Shorted wiring or connectors
• Faulty passenger side mirror assembly
• Damaged or frayed wires
• Corroded connectors
• Malfunctioning control module
• Improper installation or modifications
• Water intrusion or moisture damage

Common misdiagnosis for B1641 Mirror Passenger Left Circuit Short To Battery

• Faulty passenger side mirror
• Wiring harness issues
• Short circuit in the electrical system
• Malfunctioning body control module (BCM)
• Defective switch or control module
• Grounding issues
• Incorrectly installed aftermarket accessories

Common Troubleshooting Steps

The OBD-II code B1641 indicates a problem with the passenger side mirror circuit, specifically a short to battery in the left mirror circuit. Here are some common troubleshooting steps to diagnose and resolve this issue:

• Visual Inspection:
• Check the wiring harness and connectors leading to the passenger side mirror for any visible damage, fraying, or corrosion.
• Inspect the mirror assembly for any signs of physical damage or water intrusion.
• Check Fuses:
• Locate the fuse box and check the fuses related to the power mirrors. Replace any blown fuses and see if the code persists.
• Test the Mirror Motor:
• Disconnect the mirror from the wiring harness and test the mirror motor directly with a multimeter or by applying power from a known good source. If the motor operates correctly, the issue may lie in the wiring or control module.
• Check for Shorts:
• Use a multimeter to check for continuity in the mirror circuit. Look for any shorts to ground or battery voltage. This can be done by measuring resistance between the mirror circuit wires and the vehicle chassis or battery positive.
• Inspect the Control Module:
• If applicable, check the power mirror control module for faults. This may involve checking for proper voltage and ground at the module and ensuring it is functioning correctly.
• 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.
• Repair or Replace Damaged Components:
• If any damaged wiring, connectors, or components are found during the inspection, repair or replace them as necessary.
• Clear Codes and Test Drive:
• After making repairs, clear the trouble codes using an OBD-II scanner and take the vehicle for a test drive to see if the code returns.
• Consult Service Manual:
• If the issue persists, consult the vehicle’s service manual for specific wiring diagrams and troubleshooting procedures related to the power mirror system.
• Professional Diagnosis:
• If you are unable to resolve the issue, 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 identify and resolve the issue related to the B1641 code.