P0A18Motor Torque Sensor Circuit Range/Performance
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- The motor torque sensor delivers an electrically valid signal, but the torque it reports does not match what the control unit expects from the commanded motor current, speed and operating state. Typical checks compare measured and estimated torque or look for an offset when no torque is applied. Honda patents show such a sensor mounted inside the hollow output shaft of a traction motor, where electromagnetic noise is a known accuracy issue. No manufacturer documents P0A18 publicly. CARB requires approved monitoring of drive motor faults that impair propulsion. P0A17 is the plain circuit fault; P0A19 and P0A20 are out of range low and high. The drive system usually limits electric torque.
- What you may notice
- Hybrid system warning light
- Reduced or uneven electric assistance
- Engine runs more often, fuel use rises
- Likely causes
- LikelySensor offset or gain drifted, reading off against the torque model
- PossibleElectrical interference on the signal from damaged shielding or ground
- PossibleMissing or outdated calibration after module or drive unit replacement
- RareMechanical fault in the drive unit that changes the real torque
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €100 – €3,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.