WOMS
U code network Medium severity

U1249 SCP (J1850) Invalid or Missing Data for Time / Date

The OBD2 code U1249 indicates that there is invalid or missing data related to the time or date in the vehicle's communication network, specifically within the SCP (J1850) protocol

Definition

The OBD2 code U1249 indicates that there is invalid or missing data related to the time or date in the vehicle's communication network, specifically within the SCP (J1850) protocol

Common causes

  • Faulty or disconnected battery
  • Malfunctioning PCM (Powertrain Control Module)
  • Corrupted or missing data in the vehicle's computer
  • Issues with the vehicle's wiring or connectors
  • Faulty or damaged sensors
  • Software glitches or outdated firmware
  • Problems with the OBD-II port or communication lines
  • Electrical interference or grounding issues

Common misdiagnoses

  • Faulty PCM (Powertrain Control Module)
  • Bad battery or poor battery connections
  • Corrupted software or firmware in the vehicle's computer
  • Faulty or damaged wiring harness
  • Malfunctioning instrument cluster
  • Issues with the vehicle's clock or timekeeping system
  • Problems with the OBDII connector or communication lines
  • Incorrectly set or malfunctioning time zone settings

Troubleshooting steps

  1. 1. Check for Additional Codes

    Use an OBD-II scanner to check for any other trouble codes that may be present. Sometimes, multiple codes can provide more context for the issue

  2. 2. Inspect the Battery and Charging System

    Ensure that the vehicle's battery is in good condition and fully charged. A weak battery can cause communication issues

  3. 3. Check the alternator and charging system to ensure they are functioning properly

  4. 4. Examine the Wiring and Connectors

    Inspect the wiring and connectors related to the SCP (J1850) communication network. Look for signs of damage, corrosion, or loose connections

  5. 5. Pay special attention to the connectors at the PCM (Powertrain Control Module) and any other modules that communicate on the SCP network

  6. 6. Check the Ground Connections

    Ensure that all ground connections related to the PCM and other modules are clean, tight, and free of corrosion. Poor ground connections can lead to communication issues

  7. 7. Test the Communication Network

    Use a scan tool to monitor the data bus for communication between modules. Check if other modules are responding correctly

  8. 8. If possible, use an oscilloscope to check the signal integrity on the J1850 bus

  9. 9. Inspect the PCM

    If the above steps do not resolve the issue, consider testing or replacing the PCM. A faulty PCM can cause communication errors

  10. 10. Ensure that the PCM is properly programmed and configured for the vehicle

  11. 11. Check for Software Updates

    Verify if there are any software updates available for the PCM or other modules. Sometimes, manufacturers release updates to fix known issues

  12. 12. Clear the Codes and Test Drive

    After performing the 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

  13. 13. Consult Technical Service Bulletins (TSBs)

    Check for any TSBs related to the U1249 code for your specific vehicle make and model. Manufacturers may have specific recommendations or known fixes

  14. 14. Seek Professional Help

    If you are unable to resolve the issue after following these steps, it may be best to consult a professional mechanic or technician who has experience with your vehicle's specific systems. By following these troubleshooting steps, you should be able to identify the root cause of the U1249 code and take appropriate action to resolve it