LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Kia >> 2017 >> Optima Plug-In Hybrid EX >> Repair and Diagnosis >> Transmission >> Automatic Trans >> Automatic Transaxle System Diagnosis (PHEV) >> DTC U1004: Lost Communication With Hybrid Powertrain Control Module (H-CAN) >> DTC Information >> DTC Detecting Condition
April 5, 2026: LEMON Manuals is launched! Read the announcement.

DTC Information: DTC Detecting Condition

Item Detecting Condition Possible Cause
DTC Strategy
  • CAN Communication Monitoring
  1. Poor Connector Connection
  2. Faulty H-CAN Communication Circuit
  3. Faulty HCU
Enable Conditions
  • 0.5s after PCM turns "ON"
  • Ignition "ON" voltage between 9V and 16V
Threshold value
  • No Message from HCU
Fail safe
  • Limp Home Driving
Detecting Time
  • 2s
MIL ON Condition
  • 2 Driving Cycles
scientia non olet · About LEMON Manuals