P0A59Generator Current Sensor Circuit
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P0A59 is the general circuit fault of the current sensor on the hybrid generator, the electric machine driven by the engine that charges the battery and often starts the engine. Its inverter uses the current reading to control generator torque. No manufacturer documents P0A59 publicly with criteria. Patents describe the same sensing on generators: Toyota for a motor that also works as an engine-driven generator, Hyundai for the hybrid starter-generator, where two phases are measured and the third is calculated, and Caterpillar for generator and traction motor sensors. CARB requires circuit checks of hybrid input components. P0A5A is plausibility, P0A5B/P0A5C low and high. Without a valid reading the generator is disabled, so charging and engine start can be affected.
- What you may notice
- Hybrid warning and MIL
- Engine runs constantly or the high-voltage battery is no longer charged
- Vehicle may not enter ready mode
- Likely causes
- LikelyGenerator current sensor failed (usually inside the inverter)
- PossibleSensor supply or signal line interrupted or shorted
- RareEvaluation circuit on the generator control board faulty
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €300 – €4,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.