P0AC4

What does P0AC4 mean?

Fault code P0AC4 means "Hybrid Powertrain Control Module Requested MIL Illumination". It is an EV/Hybrid-specific diagnostic trouble code (DTC) in the powertrain system, classified as "motor" with a severity level of "warning". This code indicates a condition that should be addressed soon. Schedule a diagnostic appointment within the next few days to prevent further damage. This code is defined by the SAE J2012 / ISO 15031-6 standard and applies to OBD-II compliant vehicles sold in the US, EU, and other global markets. [Ford EV-specific: High Voltage Battery Positive Contactor Control Circuit/Open. Applies to: Mustang Mach-E, F-150 Lightning, E-Transit] [Volkswagen EV-specific: High Voltage Battery Positive Contactor Control Circuit/Open. Applies to: ID.3, ID.4, ID.5] [BMW EV-specific: HV Battery Positive Contactor Control Circuit Open. Applies to: BMW i4 (2022+), BMW iX1 (2022+), BMW iX3 (2020+), BMW i5 (2023+), BMW iX (2021+)] [General Motors EV-specific: HV Battery Positive Contactor Open Circuit. Applies to: Chevrolet Equinox EV (2024+), Chevrolet Blazer EV (2024+), Honda Prologue (2024+), Cadillac Lyriq (2023+), Chevrolet Silverado EV (2024+)] [Volkswagen Group (MEB) EV-specific: HV Battery Positive Contactor Control Circuit Open. Applies to: VW ID.3, VW ID.4, VW ID.5, VW ID.7] [Audi EV-specific: HV Battery Positive Contactor Open. Applies to: Audi Q6 e-tron (2024+), Audi SQ6 e-tron (2024+), Porsche Macan EV (2024+), Audi Q4 e-tron (2021+), Audi Q4 Sportback e-tron (2021+)]

Possible Causes

• Electric motor winding fault
• Inverter control module failure
• Position sensor misalignment or failure
• Overheating due to cooling system issue

Recommended Actions

1. 1 Schedule service as soon as possible
2. 2 Schedule a diagnostic scan at an authorized service center
3. 3 Avoid driving at high speeds until inspected