P0A17: Motor Torque Sensor Circuit
What to do
Expect reduced power rather than a breakdown — the system is being deliberately cautious about torque it cannot verify. Have it diagnosed before a long trip. The parts involved live on the high-voltage side of the car: do not unplug or probe anything with orange cabling yourself.
What this code means
The circuit reporting the drive motor's torque has failed its plausibility checks.
Why a torque reading gets its own fault family at all: an electric motor delivers its full twist instantly, with no revs to climb and no clutch to slip. Unintended torque on a machine like that is unintended acceleration, so the module cross-checks the torque it commanded against the torque the measuring chain says was delivered, continuously. When the two disagree — or the reading itself stops making sense — the module does not wait to find out which side is lying. It reduces power and stores this code.
On most hybrids there is no torque sensor to replace. The value is computed from the phase currents and the rotor angle rather than measured by a discrete part, so the code points at a measuring chain — current sensors, position sensor, the wiring between the transaxle and the inverter, and the inverter's own electronics. A quote for a "torque sensor" on a car that computes the value is a quote for a part that does not exist; what actually gets tested is the chain.
Likely causes
Start here
- Corroded or loose connector · easy
- Open circuit in sensor wiring · moderate
Less common
- Chafed harness between transaxle and inverter · moderate
- Faulty motor torque sensor · specialist
- Faulty power inverter · specialist
Symptoms
Components involved
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
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