U1299 – Lost Communication with Hybrid Powertrain Control Module (HPCM) A.

The ODBII code U1299 indicates a loss of communication with the Hybrid Powertrain Control Module (HPCM) A, which may affect the vehicle’s hybrid system functionality.

The severity of ODBII code U1299 is moderate to severe.

Common Causes For: U1298 U1298: “Control Module Communication Failure”

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

Common misdiagnosis for U1299 Lost Communication with Hybrid Powertrain Control Module (HPCM) A.

• Faulty Hybrid Powertrain Control Module (HPCM)
• Wiring issues or damaged connectors
• Faulty Engine Control Module (ECM)
• Battery management system problems
• Communication network issues (CAN bus)
• Faulty sensors related to the hybrid system
• Software or firmware issues in the control modules
• Grounding problems in the electrical system

Common Troubleshooting Steps

When dealing with the OBD-II code U1299, which indicates “Lost Communication with Hybrid Powertrain Control Module (HPCM) A,” there are several common troubleshooting steps you can follow to diagnose and potentially resolve the issue. Here’s a structured approach:

• Check for Additional Codes: Use an OBD-II scanner to check for any other trouble codes that may be present. Codes related to other modules can provide context for the U1299 code.
• 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.
• **Connector Pins: Ensure that the pins in the connectors are not bent, corroded, or damaged.
• 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.
• **Ground Connections: Ensure that the ground connections for the HPCM are secure and free of corrosion.
• 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.
• **Termination Resistors: Ensure that the CAN bus has the correct termination resistors in place.
• Test the HPCM: If the wiring and connections are intact, the HPCM itself may be faulty. You can test the module by:
• **Reprogramming or Resetting: Sometimes, reprogramming or resetting the module can resolve communication issues.
• **Substituting with a Known Good Module: If possible, replace the HPCM with a known good unit to see if the issue persists.
• 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.
• Inspect Other Modules: Since the HPCM communicates with other modules, check for issues in related modules (e.g., Engine Control Module, Transmission Control Module) that may affect communication.
• Clear Codes and Test Drive: After performing the above checks and repairs, clear the trouble codes and take the vehicle for a test drive to see if the code returns.
• Consult Technical Service Bulletins (TSBs): Look for any TSBs related to the U1299 code or the specific vehicle make and model. Manufacturers may have documented common issues and fixes.
• Seek Professional Help: If the issue persists after all troubleshooting steps, it may be necessary to consult a professional mechanic or dealership for further diagnosis. By following these steps, you should be able to identify the root cause of the U1299 code and take appropriate action to resolve the communication issue with the Hybrid Powertrain Control Module.