U1695 – Lost Communication with Body Control Module.

The ODBII code U1695 indicates a loss of communication between the vehicle’s control module and the body control module, suggesting a potential issue with wiring, connectors, or the module itself.

The severity of ODBII code U1695 is moderate.

Common Causes For: U1694 Lost Communication with Body Control Module (BCM)”.

• Faulty Body Control Module (BCM)
• Damaged wiring or connectors
• Corroded terminals
• Poor ground connection
• Faulty communication network (CAN bus issues)
• Blown fuses
• Software issues or programming errors
• Other module failures affecting communication

Common misdiagnosis for U1695 Lost Communication with Body Control Module.

• Faulty Body Control Module (BCM)
• Wiring issues or shorts in the communication lines
• Defective or corroded connectors
• Issues with the power supply to the BCM
• Faulty Instrument Cluster
• Malfunctioning Engine Control Module (ECM)
• Problems with other control modules in the network
• Software or firmware issues in the BCM or other modules

Common Troubleshooting Steps

When dealing with the OBD-II code U1695, which indicates “Lost Communication with Body Control Module,” there are several common troubleshooting steps you can follow to diagnose and potentially resolve the issue. Here’s a structured approach:

• Check for Other Codes: Use an OBD-II scanner to check for any additional trouble codes. Other codes may provide more context or indicate related issues.
• Inspect the Wiring and Connectors: **Visual Inspection: Check the wiring harness and connectors related to the Body Control Module (BCM) for any signs of damage, corrosion, or loose connections.
• **Connector Pins: Ensure that the pins in the connectors are not bent, corroded, or damaged.
• Check Power and Ground: **Power Supply: Verify that the BCM is receiving the correct voltage. Use a multimeter to check the power supply to the module.
• **Ground Connections: Ensure that the ground connections for the BCM are secure and free of corrosion.
• Inspect the Body Control Module: **Physical Condition: Check the BCM for any signs of physical damage or water intrusion.
• **Reprogramming: If the BCM has been replaced, ensure that it has been properly programmed to the vehicle.
• Test Communication Lines: **CAN Bus Communication: Use a scan tool to check if the BCM is communicating with other modules on the CAN bus. If other modules are also not communicating, the issue may be with the bus itself.
• **Scope Testing: If available, use an oscilloscope to check the data lines for proper signal patterns.
• Check for Short Circuits: Inspect the wiring for any short circuits that may be affecting communication. This can include shorts to power or ground.
• Look for Environmental Factors: Consider if there have been any recent changes or repairs to the vehicle that could have affected the BCM or its wiring (e.g., bodywork, water leaks).
• Reset the Codes: After performing checks and repairs, clear the codes using the OBD-II scanner and see if the code returns after a test drive.
• Consult Technical Service Bulletins (TSBs): Check for any manufacturer-specific TSBs related to the U1695 code or BCM issues for your vehicle make and model.
• Seek Professional Help: If the issue persists after performing these steps, it may be necessary to consult a professional mechanic or automotive technician who has experience with your specific vehicle. By following these steps, you can systematically diagnose the cause of the U1695 code and take appropriate action to resolve the communication issue with the Body Control Module.