U2529 – refers to a communication issue between control modules, specifically indicating a problem with the High Speed CAN Bus.

The ODBII code U2529 indicates a communication issue between control modules due to a malfunction in the High Speed CAN Bus, which may affect data transmission and functionality of connected systems.

The severity of ODBII code U2529 is generally considered moderate to severe, as it indicates a communication issue that can affect multiple control modules and vehicle functionality.

Common Causes For: U2528 U2528: “Control Module Communication Failure”

• Faulty wiring or connectors in the High Speed CAN Bus circuit.
• Short circuits or open circuits in the CAN Bus wiring.
• Malfunctioning control modules (e.g., ECM, TCM).
• Corroded or damaged connectors.
• Interference from aftermarket devices or modifications.
• Poor ground connections.
• Software issues or bugs in the control modules.
• Faulty termination resistors in the CAN Bus network.

Common misdiagnosis for U2529 refers to a communication issue between control modules, specifically indicating a problem with the “High Speed CAN Bus.

• Faulty control module
• Bad wiring or connectors
• Power supply issues
• Grounding problems
• Intermittent short circuits
• Faulty sensors
• Software glitches or updates needed
• Incorrectly installed aftermarket accessories
• Corroded terminals
• Issues with the low-speed CAN bus

Common Troubleshooting Steps

The OBD-II code U2529 indicates a communication issue on the High-Speed CAN (Controller Area Network) bus, which is used for communication between various control modules in a vehicle. Here are some common troubleshooting steps to diagnose and resolve this issue:

• Check for Other Codes: Scan the vehicle for any additional trouble codes. Other codes may provide more context or indicate which module is having issues.
• Inspect Wiring and Connectors: **Visual Inspection: Check the wiring harnesses and connectors associated with the High-Speed CAN bus 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.
• Test the CAN Bus Voltage: Use a multimeter to measure the voltage on the CAN High and CAN Low wires. The typical voltage levels should be around 2.5V when the bus is idle.
• Check for proper voltage levels while the vehicle is running.
• Check for Short Circuits: Inspect the CAN bus wiring for any short circuits to ground or to each other. This can cause communication failures.
• Disconnect Modules: If multiple modules are connected to the CAN bus, disconnect them one at a time to isolate the faulty module. After disconnecting a module, clear the codes and see if the U2529 code returns.
• Test Individual Modules: If a specific module is suspected, test it for proper operation. This may involve checking its power and ground connections, as well as its ability to communicate on the CAN bus.
• Check for Interference: Ensure that there are no aftermarket devices (like alarms, radios, etc.) that could be interfering with the CAN bus communication.
• Use a CAN Bus Scanner: If available, use a specialized CAN bus scanner to monitor the communication on the bus. This can help identify if specific messages are missing or if there are communication errors.
• Inspect the Ground Connections: Ensure that all ground connections for the control modules are secure and free of corrosion. Poor grounding can lead to communication issues.
• Update or Reprogram Modules: In some cases, a software update or reprogramming of the affected control module(s) may be necessary to resolve communication issues.1
• Consult Service Manual: Refer to the vehicle’s service manual for specific wiring diagrams and troubleshooting procedures related to the CAN bus system.1
• Seek Professional Help: If the issue persists after performing these steps, it may be necessary to consult a professional mechanic or technician with experience in automotive electronics and CAN bus systems. By following these steps, you should be able to identify and resolve the communication issue indicated by the U2529 code.