U1505 – Body Control Module Communication Error

The ODBII code U1505 indicates a communication error between the Body Control Module (BCM) and other control modules in the vehicle, suggesting a potential issue with wiring, connectors, or the BCM itself.

The severity of ODBII code U1505 is moderate.

Common Causes For: U1504 U1504: Transmission Control Module Communication Error

• Faulty Body Control Module (BCM)
• Damaged wiring or connectors
• Poor ground connections
• Corroded terminals
• Faulty communication network (CAN bus issues)
• Software glitches or outdated firmware
• Interference from aftermarket accessories
• Low battery voltage or weak battery
• Faulty or damaged sensors connected to the BCM

Common misdiagnosis for U1505 U1505: Body Control Module Communication Error

• Faulty Body Control Module (BCM)
• Wiring issues or shorts in the communication lines
• Faulty or corroded connectors
• Malfunctioning Instrument Cluster
• Defective Powertrain Control Module (PCM)
• Battery or charging system issues
• Grounding problems
• Faulty sensors or actuators related to the BCM
• Software or firmware issues in the BCM
• Other communication errors with related modules

Common Troubleshooting Steps

When dealing with OBD-II code U1505, which indicates a Body Control Module (BCM) communication error, 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 related trouble codes. Sometimes, multiple codes can provide more context for the issue.
• Inspect Wiring and Connectors: **Visual Inspection: Check the wiring harness and connectors related to the BCM for any signs of damage, corrosion, or loose connections.
• **Connector Pins: Ensure that the pins in the connectors are not bent or corroded.
• 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 Communication Lines: **CAN Bus: If your vehicle uses a Controller Area Network (CAN) bus, check the communication lines for continuity and proper resistance.
• **Network Issues: Look for any issues with other modules on the network that may be affecting communication.
• Test the BCM: If possible, test the BCM using a scan tool that can communicate with the module. Check for any response or data that the BCM should provide.
• If you have access to a known good BCM, you can swap it temporarily to see if the issue resolves.
• Check for Software Updates: Sometimes, manufacturers release software updates for the BCM. Check with the dealership or manufacturer to see if there are any updates available.
• Clear Codes and Test Drive: After performing the above checks and repairs, clear the trouble 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 U1505 code for your specific vehicle make and model. Manufacturers may have specific recommendations for addressing this issue.
• Seek Professional Help: If you are unable to resolve the issue after these steps, it may be necessary to consult a professional mechanic or an automotive electrician who has experience with BCM issues. By following these steps, you should be able to identify the root cause of the U1505 code and take appropriate action to resolve it.