What it means
The ECM detects a circuit range/performance fault on the drive motor inverter temperature sensor a circuit. Reading cannot be used reliably for control.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
Drive motor inverter temperature sensor A measures the temperature of a monitored area in the inverter. The control module checks whether sensor A's signal changes plausibly with operating conditions; this code sets when its reading is out of the expected range or response, even if the sensor circuit is not electrically open or shorted.
Common causes
Most likely first.
- Sensor characteristic drifted
- Sensor mounting displaced
- Sensor element aged beyond calibration window
Symptoms
- EV/hybrid system warning light on
- Reduced motor power or torque
- Possible limp mode or vehicle shutdown
How to diagnose it
- Review freeze-frame data and live inverter temperatures to identify the conditions when sensor A's reading became implausible.
- Compare sensor A with other available inverter temperature readings as the system warms to look for an outlier or a response that is too slow.
- With the vehicle powered down as specified by the manufacturer, inspect sensor A's mounting, connector, and wiring for displacement, damage, or poor contact.
- Check the sensor A circuit and signal using the manufacturer's wiring information to rule out an open, short, or connection problem.
- Test sensor A's response and mounting against the manufacturer's specification, and inspect for related inverter cooling faults.
Common fixes
- Secure sensor A in its specified position.
- Repair a poor sensor A connector or damaged wiring.
- Replace sensor A if its temperature response is outside the manufacturer's specification.
- Repair any confirmed inverter cooling problem.
Can I keep driving?
Drive gently and avoid high loads if the vehicle has reduced motor power; stop safely if a drive system warning appears or propulsion becomes unreliable. An implausible temperature reading can cause protective power limits or shutdown.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.