P0A2A: Drive Motor A Temperature Sensor A Circuit
What to do
Expect the car to be conservative with electric power while this is stored — that is deliberate. Diagnosis starts at the wiring and connector outside the transaxle, which is the cheap half of the circuit; the sensor itself is internal and is the last suspect, not the first.
What this code means
The drive motor's temperature sensor circuit has failed — the thermistor buried in the motor's windings is reading open, shorted or implausible.
An electric motor's enemy is heat in its winding insulation, and the module manages that heat actively: it derates power as temperature climbs, long before damage. This sensor is what makes that protection possible, so losing it forces a choice between running blind and assuming the worst. Vehicles assume the worst — expect earlier, more cautious power reduction while this code is stored, especially in sustained electric running.
Keep the circuit codes and the temperature codes apart. This family (P0A2A–P0A2E) says the reading failed; P0A2F says the motor genuinely got hot. It is the same distinction the transmission range draws between a pressure circuit fault and pressure actually being low — one is an electrical diagnosis, the other a thermal one, and they lead different places.
The sensor itself lives inside the transaxle, which makes the wiring the good news: the run between the transaxle and the inverter fails far more often than the thermistor, and it is reachable without opening anything.
Likely causes
Start here
- Open circuit in sensor wiring · moderate
- Corroded or loose connector · easy
Less common
- Chafed harness between transaxle and inverter · moderate
- Faulty motor temperature sensor · 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.
Community experience
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