Reference meaning
What does this code mean?
The wording below belongs to the named make and communication. Match the complete code, reporting module, model year and engine before applying it.
A code identifies a detected condition, not a part that must automatically be replaced.
Narrow by vehicle
A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.
Before replacing a part
Record codes and freeze-frame data. Check battery condition, related codes and visible wiring or hose damage. Follow the vehicle's diagnostic procedure and test results before replacing parts.
Scan worksheet →Manufacturer wording
Source wording can vary by vehicle and suffix. It is shown as written, not as a universal diagnosis.
P0AC4Hybrid/EV Powertrain Control Module Requested MIL Illumination
Manufacturer communications
9Original wording in English
CADILLAC
This Preliminary Information communication provides information to the technician the steps to diagnose and repair vehicles that have Check Engine Light illuminated with an "Engine Unavailable" and "Reduced Propulsion" messages on the Driver Information Center. Technician may find Diagnostic Trouble Codes a P0AB9 and P0AC4. Tech…
CADILLAC
This Preliminary Information communication provides information to the technician the steps to diagnose and repair vehicles that have Check Engine Light illuminated with an "Engine Unavailable" and ?Reduced Propulsion? messages on the Driver Information Center. Technician may find Diagnostic Trouble Codes a P0AB9 and P0AC4. Tech…
CHEVROLET
This Bulletin provides ECM reprogramming information to Correct DTC P3260 and P0AC4.
CHEVROLET
This Preliminary information communicates to dealers on how to diagnose and repair the vehicle if it setsDiagnostic trouble codes P0AC4 (ECM) and P2797 (HPCM)
Check vehicle applicability
14A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.
Can I keep driving?
A code alone cannot establish whether driving is safe. A flashing malfunction light, severe shaking, overheating, oil-pressure warning or loss of braking or steering needs prompt attention. Stop in a safe place and seek assistance when control or engine safety is affected. Follow the vehicle handbook.