U2699 – Lost Communication with Vehicle Dynamics Control Module.

The ODBII code U2699 indicates a loss of communication with the Vehicle Dynamics Control Module, which may affect the vehicle’s stability and traction control systems.

The severity of ODBII code U2699 is generally considered moderate to severe.

Common Causes For: U2698 U2698: Control Module Communication Bus Fault

• Faulty Vehicle Dynamics Control Module (VDCM)
• Damaged or corroded wiring or connectors
• Poor ground connection
• Faulty communication lines (CAN bus issues)
• Software or firmware issues in the VDCM
• Malfunctioning related sensors (e.g., wheel speed sensors)
• Battery or power supply issues affecting the VDCM
• Intermittent electrical connections

Common misdiagnosis for U2699 Lost Communication with Vehicle Dynamics Control Module.

• Faulty ABS module
• Defective wheel speed sensors
• Malfunctioning engine control module (ECM)
• Wiring issues or shorts in the communication lines
• Bad ground connections
• Faulty powertrain control module (PCM)
• Incorrectly diagnosed transmission issues
• Battery or charging system problems
• Faulty or corroded connectors
• Software or firmware issues in the vehicle’s control modules

Common Troubleshooting Steps

When dealing with the OBD-II code U2699, which indicates “Lost Communication with Vehicle Dynamics 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. Sometimes, other codes can provide context or indicate related issues.
• Inspect the Wiring and Connectors: **Visual Inspection: Check the wiring harness and connectors associated with the Vehicle Dynamics Control Module (VDCM) 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 VDCM is receiving the correct voltage. Use a multimeter to check the power supply to the module.
• **Ground Connection: Ensure that the ground connection for the VDCM is secure and functioning properly.
• Inspect the Vehicle Dynamics Control Module: **Module Condition: Check the VDCM for any physical damage or signs of failure.
• **Reprogramming: If applicable, consider reprogramming or updating the module’s software, as a software glitch can sometimes cause communication issues.
• Check for Communication Issues: **CAN Bus Communication: Since the VDCM communicates over the CAN bus, check for issues with the CAN bus wiring and other modules on the bus.
• **Network Integrity: Use a scan tool to monitor the CAN bus for any irregularities or communication failures with other modules.
• Perform a Hard Reset: Disconnect the vehicle’s battery for a few minutes to reset the vehicle’s electronic systems. Reconnect and see if the code reappears.
• Test the Module: If possible, test the VDCM in another vehicle (if you have access to one) to determine if the module itself is faulty.
• Consult Technical Service Bulletins (TSBs): Check for any TSBs related to the specific make and model of your vehicle. Manufacturers may have issued guidance on common issues related to the VDCM.
• Seek Professional Help: If the issue persists after performing the above steps, it may be necessary to consult a professional mechanic or technician who has experience with your vehicle’s specific systems.
• Document Findings: Keep a record of any tests performed, findings, and repairs made. This documentation can be helpful for future reference or if you need to consult a professional. By following these steps, you should be able to identify the root cause of the U2699 code and take appropriate action to resolve the communication issue with the Vehicle Dynamics Control Module.