WOMS
U code network Medium severity

U1140 SCP (J1850) Invalid or Missing Data for Gateway

The OBD2 code U1140 SCP (J1850) indicates that there is invalid or missing data being communicated through the vehicle's gateway, which may affect the operation of various systems relying on that data

Definition

The OBD2 code U1140 SCP (J1850) indicates that there is invalid or missing data being communicated through the vehicle's gateway, which may affect the operation of various systems relying on that data

Common causes

  • Faulty gateway module
  • Poor or damaged wiring/connectors
  • Communication issues between modules
  • Corrupted software or firmware in the gateway
  • Incompatible or malfunctioning aftermarket devices
  • Low battery voltage or power supply issues
  • Faulty sensors or modules sending incorrect data

Common misdiagnoses

  • Faulty Gateway Module
  • Wiring Issues
  • Corrupted Software/Firmware
  • Faulty Sensor
  • Battery Voltage Issues
  • Communication Network Problems
  • Faulty ECM/PCM
  • Incorrectly Installed Aftermarket Accessories

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 other codes may resolve the U1140 code

  2. 2. Inspect Wiring and Connectors

  3. 3. Visually inspect the wiring and connectors related to the gateway module and the communication lines (SCP/J1850)

  4. 4. Look for signs of damage, corrosion, or loose connections that could affect communication

  5. 5. Check Battery Voltage

    Ensure that the vehicle's battery is fully charged and that the voltage is within the normal range (typically 12.4 to 12.6 volts). Low voltage can cause communication issues

  6. 6. Test the Gateway Module

  7. 7. If accessible, test the gateway module for proper operation. This may involve checking for power and ground at the module and ensuring it is functioning correctly

  8. 8. If the module is faulty, it may need to be replaced

  9. 9. Inspect Other Modules

    Since the gateway module communicates with other modules, check the functionality of other modules in the network. A malfunctioning module can cause communication issues

  10. 10. Check for Short Circuits or Open Circuits

    Use a multimeter to check for shorts or open circuits in the communication lines. This may involve checking the resistance and continuity of the wires

  11. 11. Scan for Communication Issues

    Use a professional-grade scan tool to monitor communication between modules. This can help identify if specific modules are not communicating properly

  12. 12. Clear Codes and Test Drive

    After performing inspections and repairs, clear the trouble codes 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 U1140 code for your specific vehicle make and model. Manufacturers may have specific recommendations or known issues

  14. 14. Seek Professional Help

    If the issue persists after performing these steps, it may be necessary to consult a professional mechanic or technician who has experience with your vehicle's specific systems. By following these troubleshooting steps, you can systematically identify and address the underlying cause of the U1140 code