WOMS
U code network High severity

U1118 Lost Communication with Vehicle Dynamics Control Module

The OBD2 code U1118 indicates a loss of communication between the vehicle's onboard diagnostic system and the Vehicle Dynamics Control Module, which may affect systems related to stability and traction control

Definition

The OBD2 code U1118 indicates a loss of communication between the vehicle's onboard diagnostic system and the Vehicle Dynamics Control Module, which may affect systems related to stability and traction control

Common causes

  • Faulty Vehicle Dynamics Control Module (VDCM)
  • Damaged or corroded wiring or connectors
  • Poor ground connection
  • Faulty communication network (CAN bus issues)
  • Malfunctioning or disconnected sensors
  • Software or firmware issues in the VDCM
  • Battery or power supply problems
  • Interference from aftermarket modifications or devices

Common misdiagnoses

  • Faulty ABS module
  • Wiring issues or shorts
  • Defective wheel speed sensors
  • Malfunctioning engine control module (ECM)
  • Incorrectly diagnosed transmission issues
  • Power supply problems
  • Faulty brake control module
  • Software or firmware issues in the control modules

Troubleshooting steps

  1. 1. 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

  2. 2. Inspect the Wiring and Connectors

    Visual Inspection: Check the wiring harness and connectors related to the Vehicle Dynamics Control Module (VDCM) for any signs of damage, corrosion, or loose connections

  3. 3. Connector Pins

    Ensure that the pins in the connectors are not bent, corroded, or damaged

  4. 4. 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

  5. 5. Ground Connection

    Ensure that the ground connection for the VDCM is secure and functioning properly

  6. 6. Inspect the Vehicle Dynamics Control Module

    Module Condition: If possible, check the condition of the VDCM itself. Look for any signs of physical damage or water intrusion

  7. 7. Reprogramming

    In some cases, the module may need to be reprogrammed or updated with the latest software

  8. 8. Check for Communication Issues

    CAN Bus Communication: The VDCM communicates over the CAN bus. Use a scan tool to check if other modules are communicating properly. If other modules are also not communicating, there may be a problem with the CAN bus itself

  9. 9. Termination Resistors

    Ensure that the CAN bus termination resistors are present and functioning correctly

  10. 10. Perform a Hard Reset

    Disconnect the vehicle's battery for a few minutes to reset the modules. Reconnect and see if the code reappears

  11. 11. Test the VDCM

    If you have access to a compatible scan tool, you can perform a functional test of the VDCM to see if it responds to commands

  12. 12. Check for Environmental Factors

    Sometimes, environmental factors such as moisture or extreme temperatures can affect module performance. Ensure that the module is not exposed to conditions that could cause failure

  13. 13. 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

  14. 14. 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.Conclusion Troubleshooting a U1118 code involves a systematic approach to check for communication issues, inspect wiring and connections, and verify the functionality of the Vehicle Dynamics Control Module. Always refer to the vehicle's service manual for specific procedures and specifications