What it means
The ECM detects a circuit high 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 the temperature around the generator-side power electronics so the ECM can manage hybrid operation and protect them from heat. This code sets when the sensor A circuit voltage is above its expected range, which can happen with a signal short to battery voltage or an open sensor circuit.
Common causes
Most likely first.
- Signal wire shorted to B+
- Open sensor
- Connector pins corroded - high contact resistance
Symptoms
- Hybrid-system warning light may illuminate
- Reduced power or limited hybrid operation
- Temperature-related protective operation may occur
How to diagnose it
- Save freeze-frame data and compare sensor A's live reading with other inverter temperatures to determine whether it is implausibly high or fixed at an extreme.
- With the vehicle powered down as specified by the manufacturer, inspect the generator inverter sensor A connector for corrosion, loose fit, or damaged pins.
- Inspect the sensor A signal wire for damage or contact with a power feed, and check the harness for an open circuit.
- Test the sensor A circuit for an unintended connection to battery voltage and check continuity using the manufacturer's wiring information.
- Test the sensor A element and circuit response against the manufacturer's specification, then verify the reading after repair.
Common fixes
- Clean and secure corroded or loose sensor A connector terminals where repair is appropriate.
- Repair an open or damaged wire in the generator inverter sensor A circuit.
- Repair a signal wire shorted to battery voltage.
- Replace the sensor A element if it is open or fails the manufacturer's test.
Can I keep driving?
Keep trips short and avoid hard acceleration, high speeds, or heavy loads because the hybrid system may limit generator output when it cannot trust this temperature signal. Stop safely if power becomes severely limited or a hybrid warning indicates a shutdown risk.
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.