What it means
The ECM detects a circuit intermittent/erratic fault on the generator 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
The generator inverter temperature sensor A reports temperature around the generator-side power electronics for hybrid control and heat protection. This code sets when the sensor A signal changes erratically or drops in and out instead of tracking temperature steadily, often because of a loose connection or unstable ground reference.
Common causes
Most likely first.
- Sensor connector not seated
- Noisy ground reference
- Connector with intermittent contact under vibration
Symptoms
- Hybrid-system warning light may illuminate
- Intermittent reduction in power or hybrid operation
- Temperature-related protective operation may occur
How to diagnose it
- Review freeze-frame data and graph sensor A live data to see whether the reading jumps or cuts out while other inverter temperatures remain steady.
- With the vehicle powered down as specified by the manufacturer, check that the generator inverter sensor A connector is fully seated and its terminals are clean and undamaged.
- Inspect the sensor A harness and ground reference for looseness, corrosion, chafing, or movement-related damage.
- If the manufacturer's procedure allows, monitor the sensor A circuit while gently moving the harness to identify an intermittent connection.
- Test the sensor A ground reference, wiring continuity, and sensor response against the manufacturer's specification, then confirm stable readings after repair.
Common fixes
- Reseat and secure the generator inverter sensor A connector.
- Clean or repair corroded terminals and restore a sound ground reference.
- Repair wiring that loses contact when the harness moves.
- Replace sensor A if its output remains erratic after the connector and wiring are sound.
Can I keep driving?
Use caution and avoid long or demanding trips because intermittent readings can cause sudden hybrid power reduction or protective operation. Stop safely if power becomes unpredictable or the vehicle displays a shutdown warning.
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.