P0A42Drive Motor A Position Sensor Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P0A42 is the counterpart to P0A41: a resolver line of motor A reads above its allowed range. Typical triggers are a sine, cosine or excitation wire shorted to a supply voltage, or an open coil whose line is pulled up by the bias resistors of the input circuit, which drives the converter into clipping. Kia covers it in the same Optima Hybrid 2011-13 bulletin as P0A41: intermittent MIL or hybrid service lamp, fixed by inspecting the HPCU-to-motor sub-harness for internal shorts and pin fit. Bosch patents explain why clipping alone is not enough and how the line offset reveals a short to supply or an open line. P0A3F is the general circuit fault. Expect a warning lamp and reduced or no electric drive.
- What you may notice
- Intermittent MIL or hybrid service lamp
- Electric drive disabled or vehicle not ready
- Reduced power until the fault clears
- Likely causes
- LikelyResolver wire shorted to a supply voltage inside the sub-harness (Kia Optima Hybrid)
- PossibleOpen sine or cosine line pulled high by the input circuit
- PossiblePoor pin fit or corrosion at the resolver connectors
- RareFaulty resolver input stage in the motor control unit
- 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: €150 – €3,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.