What it means
The ECM detects a circuit low 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 detected below its expected range, such as from a signal short to ground or a faulty connection.
Common causes
Most likely first.
- Signal wire shorted to ground
- Internal sensor short
- 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
- Record freeze-frame data and compare sensor A's live reading with other inverter temperature readings to see whether it is implausibly low.
- With the vehicle powered down as specified by the manufacturer, inspect the generator inverter sensor A connector for corrosion, damaged pins, or a loose fit.
- Trace the sensor A signal wiring for chafing or contact with ground, paying attention to sections near the inverter and connector.
- Check the sensor A circuit and its ground reference for a short to ground or abnormal continuity using the manufacturer's wiring information.
- Test the sensor A element and circuit response against the manufacturer's specification, then repair the confirmed fault and recheck live data.
Common fixes
- Clean and secure corroded or loose sensor A connector terminals where repair is appropriate.
- Repair a signal wire shorted to ground or damaged wiring in the sensor A circuit.
- Replace the generator inverter temperature sensor A if it tests internally shorted.
- Recheck the circuit and clear the code after the repair.
Can I keep driving?
Avoid demanding acceleration or long, steep drives because the hybrid system may limit generator output to protect the inverter. If power drops sharply or a hybrid warning escalates, stop somewhere safe; continued operation with an unreliable temperature reading can trigger further protection.
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.