OBD-II code · Powertrain (generic)
P0AC4 Hybrid/EV Powertrain Control Module Requested MIL Illumination
The hybrid powertrain control module has requested MIL illumination via the inter-module bus. Underlying fault is reported separately by the requesting module.
Is it safe to drive with P0AC4?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyDownstream fault in hybrid system
- PossibleCommunication lag - MIL request stale
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 0.5–3 h
- Emissions test
- Usually unaffected
- Parts involved
- Hybrid Powertrain Cm, Module Communication Bus
Related codes
- P0AC1Hybrid/EV Battery Pack Current Sensor A Circuit Low
- P0AC2Hybrid/EV Battery Pack Current Sensor A Circuit High
- P0AC3Hybrid/EV Battery Pack Current Sensor A Circuit Intermittent/Erratic
- P0AC5Hybrid/EV Battery Temperature Sensor B Circuit
- P0AC6Hybrid/EV Battery Temperature Sensor B Circuit Range/Performance
- P0AC7Hybrid/EV Battery Temperature Sensor B Circuit Low
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.