P0AEE

What it means

P0AEE means the hybrid or electric vehicle control unit has judged that the signal from drive motor inverter temperature sensor A is plausible electrically but does not behave as expected. The reading may be stuck, drift, or disagree with other temperature data such as the coolant temperature, the other inverter sensors or the temperature after a cold soak. The inverter uses this sensor to protect its power electronics from overheating, so the fault can lead to reduced power. Sensor location and the plausibility test vary by model, so check manufacturer data.

Symptoms

• Hybrid or EV system warning light, or a malfunction indicator lamp, on the dashboard
• Reduced power or limp mode, especially under heavy load
• Reduced or unavailable regenerative braking or electric-only driving
• Cooling fan or inverter coolant pump running harder than usual
• Intermittent loss of drive, or the car refusing to go into Ready mode
• Other inverter or drive motor temperature codes stored alongside it

Possible causes

• Faulty inverter temperature sensor, or a sensor reading that has drifted or stucklikely
• Wiring or connector fault in the sensor circuit, such as chafing, corrosion, a poor pin fit or moisture ingresslikely
• Real inverter overheating from low coolant, trapped air, a failing inverter coolant pump or a blocked cooling circuit, leading to a sensor reading that disagrees with other datapossible
• Poor thermal contact between the sensor and the power module, or an internal inverter assembly faultpossible
• Inverter or hybrid control unit fault, or an outdated calibration where the manufacturer has issued a fix for this coderare
• Low-voltage supply or earth problems affecting the sensor reference voltagerare

How to diagnose

1. Read all stored and pending codes and the freeze frame data. Note any other inverter, motor or coolant temperature codes, and the conditions when the fault set.
2. Check for relevant technical service bulletins or software updates for the specific model and engine or drive system.
3. Check the inverter coolant level and condition, and look for leaks. Confirm the coolant pump and cooling fan operate when commanded.
4. Compare live data from the inverter temperature sensors with the coolant temperature after a long cold soak. Readings should be close to each other and to ambient temperature, and should rise smoothly with load. Look for a stuck, noisy or offset value.
5. Visually inspect the sensor wiring and connectors for damage, corrosion, water ingress and pin tension. Only work on the high-voltage system if you are trained and have followed the manufacturer's isolation procedure.
6. With the ignition off and the correct isolation done, test the sensor circuit for resistance, short circuits and open circuits. Check the sensor resistance against the manufacturer's temperature specification.
7. Wiggle-test the harness while watching live data to find intermittent faults.
8. If the wiring and sensor test fine, check the inverter assembly and control unit as directed by manufacturer diagnostics.

How to fix

• Repair or replace damaged wiring, terminals or connectors in the sensor circuit.
• Replace the inverter temperature sensor, or the inverter assembly if the sensor is not serviced separately.
• Correct coolant level, bleed air from the inverter cooling circuit, and repair any leaks or a failing coolant pump.
• Restore proper thermal contact or reseat the sensor as per manufacturer procedure.
• Apply a manufacturer-issued software update if the fault is a known calibration issue, or replace the control unit if it is faulty.
• Clear the codes after repair and road test to confirm the fault does not return.

Can I keep driving?

Nearby codes

• P0AEDGenericDrive Motor Inverter Temperature Sensor A Circuit
• P0AEFGenericDrive Motor Inverter Temperature Sensor A Circuit Low