P0AC4 – Hybrid Powertrain Control Module Requested MIL Illumination

P0AC4 – Hybrid Powertrain Control Module Requested MIL Illumination

SYMPTOMS:

  • “Check Engine” light is illuminated
  • Other symptoms depend on what triggered the code

POSSIBLE CAUSES:

  • General “request” code showing the hybrid control system detected a fault — root cause is usually stored in additional trouble codes
  • Potential weak/failing module within the hybrid battery system
  • Loose, corroded, or poor electrical connection in the hybrid powertrain circuit