WOMS
U code network Medium severity

U1637 Invalid or Missing Data for Vehicle Speed

The OBD2 code U1637 indicates that the vehicle's control module has detected invalid or missing data related to vehicle speed, which may affect the performance of various systems

Definition

The OBD2 code U1637 indicates that the vehicle's control module has detected invalid or missing data related to vehicle speed, which may affect the performance of various systems

Common causes

  • Faulty vehicle speed sensor
  • Damaged wiring or connectors
  • Poor ground connection
  • Malfunctioning engine control module (ECM)
  • Issues with the transmission control module (TCM)
  • Faulty ABS module
  • Corrupted data communication between modules
  • Software glitches or updates needed in the ECM/TCM

Common misdiagnoses

  • Faulty Vehicle Speed Sensor (VSS)
  • Malfunctioning Engine Control Module (ECM)
  • Wiring issues or short circuits
  • Faulty Transmission Control Module (TCM)
  • Incorrect tire size or calibration issues
  • Problems with the ABS module
  • Issues with the instrument cluster
  • Faulty or corroded connectors and terminals

Troubleshooting steps

  1. 1. Check for Additional Codes

    Use an OBD-II scanner to check for any other trouble codes that may be present. Addressing related codes can help in diagnosing the root cause

  2. 2. Inspect Vehicle Speed Sensor (VSS)

    Visual Inspection: Check the VSS for any physical damage, loose connections, or corrosion at the connector

  3. 3. Wiring Check

    Inspect the wiring harness for any frays, breaks, or shorts that could affect the signal

  4. 4. Testing

    Use a multimeter to test the VSS for proper voltage and resistance according to the manufacturer's specifications

  5. 5. Check Module Communication

    CAN Bus Inspection: Ensure that the Controller Area Network (CAN) bus is functioning properly. Look for any damaged wiring or poor connections

  6. 6. Scan Tool Communication

    Use a scan tool to check if other modules can communicate with the engine control module (ECM) and the transmission control module (TCM)

  7. 7. Inspect Ground Connections

    Ensure that all ground connections related to the VSS and the ECM are clean, tight, and free of corrosion. Poor grounding can lead to communication issues

  8. 8. Check for Software Updates

    Verify if there are any software updates available for the vehicle's modules. Sometimes, manufacturers release updates to fix known issues

  9. 9. Test the ECM/TCM

    If the VSS and wiring are functioning correctly, the issue may lie within the ECM or TCM. Testing or reprogramming these modules may be necessary

  10. 10. Clear Codes and Test Drive

    After performing any repairs or adjustments, clear the trouble codes and take the vehicle for a test drive to see if the code reappears

  11. 11. Consult Technical Service Bulletins (TSBs)

    Check for any TSBs related to the U1637 code for your specific vehicle make and model. Manufacturers may have specific recommendations or known issues

  12. 12. Professional Diagnosis

    If the issue persists after performing the above steps, consider seeking help from a professional mechanic or dealership. They may have specialized tools and knowledge to diagnose complex issues. By following these troubleshooting steps, you should be able to identify and resolve the cause of the U1637 code. Always refer to the vehicle's service manual for specific procedures and specifications