U1950 – Lost Communication with Body Control Module (BCM).

The ODBII code U1950 indicates a loss of communication between the vehicle’s control module and the Body Control Module (BCM), which may affect various electrical functions and systems in the vehicle.

The severity of ODBII code U1950 is generally considered moderate to severe.

Common Causes For: U1949 Lost Communication with the Hybrid Powertrain Control Module (HPCM)”.

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

Common misdiagnosis for U1950 Lost Communication with Body Control Module (BCM).

• Faulty Body Control Module (BCM)
• Wiring issues or damaged connectors
• Faulty power supply or ground connections
• Issues with other control modules
• Faulty ignition switch
• Software or firmware issues
• Corrupted data in the vehicle’s network
• Faulty CAN bus communication lines

Common Troubleshooting Steps

When dealing with OBD-II code U1950, which indicates “Lost Communication with Body Control Module (BCM),” there are several common troubleshooting steps you can follow to diagnose and potentially resolve the issue. Here’s a structured approach:

• Check for Additional Codes: Use an OBD-II scanner to check for any other trouble codes that may be present. Codes related to other modules can provide context for the U1950 code.
• Inspect the Wiring and Connectors: **Visual Inspection: Check the wiring harness and connectors leading to the BCM for any signs of damage, corrosion, or loose connections.
• **Connector Pins: Ensure that the pins in the connectors are not bent, corroded, or pushed back.
• 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 BCM.
• **Ground Connections: Ensure that the ground connections for the BCM are secure and free of corrosion.
• Inspect the BCM: **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.
• Check for Communication Issues: **CAN Bus Communication: Use a scan tool to check if other modules are communicating properly. If other modules are also showing communication issues, the problem may be with the CAN bus wiring or a central issue affecting multiple modules.
• **Network Integrity: Inspect the CAN bus wiring for shorts, opens, or interference.
• Test the BCM: If possible, test the BCM in another vehicle of the same make and model to determine if the module itself is faulty.
• Alternatively, you can try replacing the BCM with a known good unit to see if the issue resolves.
• Check for Software Updates: Check if there are any software updates available for the BCM or other related modules. Sometimes, manufacturers release updates to fix communication issues.
• Clear Codes and Test Drive: After performing the above checks and repairs, clear the codes using the OBD-II scanner and take the vehicle for a test drive to see if the code returns.
• Consult Technical Service Bulletins (TSBs): Look for any TSBs related to the U1950 code or BCM issues for your specific vehicle make and model. Manufacturers may have specific recommendations or known fixes.
• Seek Professional Help: If the issue persists after performing these steps, it may be necessary to consult a professional mechanic or an automotive electrical specialist for further diagnosis. By following these steps, you should be able to identify the root cause of the U1950 code and take appropriate action to resolve the communication issue with the Body Control Module.