WOMS
U code network High severity

U1970 Lost Communication with the Hybrid Powertrain Control Module (HPCM)"

The OBD2 code U1970 indicates that there is a loss of communication between the vehicle's onboard computer and the Hybrid Powertrain Control Module (HPCM), which can affect the operation of the hybrid system

Definition

The OBD2 code U1970 indicates that there is a loss of communication between the vehicle's onboard computer and the Hybrid Powertrain Control Module (HPCM), which can affect the operation of the hybrid system

Common causes

  • Faulty Hybrid Powertrain Control Module (HPCM)
  • Damaged or corroded wiring or connectors
  • Poor ground connections
  • Failed communication network (CAN bus issues)
  • Malfunctioning sensors related to the hybrid system
  • Software or firmware issues in the HPCM
  • Battery management system problems
  • Intermittent electrical connections

Common misdiagnoses

  • Faulty wiring or connectors
  • Bad battery or power supply issues
  • Malfunctioning Engine Control Module (ECM)
  • Issues with the Transmission Control Module (TCM)
  • Defective sensors (e.g., throttle position sensor)
  • Software or firmware issues in the control modules
  • Problems with the vehicle's CAN bus system
  • Incorrectly diagnosed hybrid battery issues

Troubleshooting steps

  1. 1. Check for Other Codes

    Use an OBD-II scanner to check for any additional trouble codes. Other codes may provide more context or indicate related issues

  2. 2. Inspect the Wiring and Connectors

    Visual Inspection: Check the wiring harness and connectors related to the HPCM 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 pushed back

  4. 4. Check the HPCM Power and Ground

    Power Supply: Verify that the HPCM is receiving the correct voltage. Use a multimeter to check the power supply to the module

  5. 5. Ground Connections

    Ensure that the ground connections for the HPCM are secure and free of corrosion

  6. 6. Inspect the Communication Network

    CAN Bus: Check the Controller Area Network (CAN) bus for continuity and proper operation. Look for any shorts or opens in the wiring

  7. 7. Termination Resistors

    Ensure that the CAN bus has the correct termination resistors in place and that they are functioning properly

  8. 8. Test the HPCM

    If possible, perform a functional test of the HPCM using a scan tool. Check for any response from the module

  9. 9. If the HPCM is suspected to be faulty, consider testing it in another vehicle (if available) or replacing it

  10. 10. Check for Software Updates

    Verify if there are any software updates available for the HPCM or the vehicle’s ECU. Sometimes, manufacturers release updates to fix communication issues

  11. 11. Inspect Related Modules

    Check other modules that communicate with the HPCM. If they are malfunctioning, they may cause communication issues

  12. 12. Look for codes in other modules that may indicate a broader communication problem

  13. 13. Clear Codes and Test Drive

    After performing inspections and repairs, clear the codes and take the vehicle for a test drive to see if the code returns

  14. 14. Consult Technical Service Bulletins (TSBs)

    Look for any TSBs related to the U1970 code or HPCM issues for your specific vehicle make and model. Manufacturers may have specific recommendations or known fixes

  15. 15. Seek Professional Help

    If the issue persists after following these steps, consider consulting a professional mechanic or dealership with experience in hybrid vehicles. They may have specialized tools and knowledge to diagnose the problem more effectively. By following these steps, you should be able to identify the root cause of the U1970 code and take appropriate action to resolve the communication issue with the Hybrid Powertrain Control Module