What it means
The ECM detects a circuit 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 monitors the temperature of a specific monitored area in the inverter that controls the drive motor. The control module checks sensor A's circuit for a usable signal; this code sets when a circuit fault makes that reading unreliable, not necessarily when the inverter is overheating.
Common causes
Most likely first.
- Sensor failed
- Wiring or connector fault
Symptoms
- EV/hybrid system warning light on
- Reduced motor power or torque
- Possible limp mode or vehicle shutdown
How to diagnose it
- Read the hybrid control module's freeze-frame data and inverter temperature live data to see when sensor A's fault occurred and whether its reading is missing or implausible.
- Compare sensor A's temperature with other available inverter temperature readings and operating conditions to check whether only this sensor is affected.
- Power down the vehicle as specified by the manufacturer, then inspect sensor A's accessible connector and wiring for damage, moisture, corrosion, or a loose fit.
- Check the sensor A circuit for continuity, shorts, and connector contact problems using the manufacturer's wiring information.
- Test sensor A against the manufacturer's specification and check for related inverter or cooling system faults.
Common fixes
- Reseat and secure the sensor A connector.
- Repair damaged or corroded sensor A wiring or connector terminals.
- Replace sensor A if it fails the manufacturer's test.
- Repair any confirmed inverter cooling fault that could affect operation.
Can I keep driving?
Avoid high-speed driving, steep climbs, and hard acceleration if power is reduced, and stop safely if the vehicle warns of a drive system fault or propulsion becomes unreliable. Inverter protection may limit power or shut the vehicle down.
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.