What it means
The control module detects an intermittent or erratic signal in the drive motor inverter temperature sensor B circuit.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
Temperature sensor B provides the control module with the drive motor inverter’s temperature signal. P0AF6 sets when that signal becomes intermittent or erratic rather than remaining stable, often because a connector or ground reference loses contact as the vehicle moves or vibrates.
Common causes
Most likely first.
- Sensor connector not seated
- Noisy ground reference
- Connector with intermittent contact under vibration
Symptoms
- EV/hybrid system warning light on
- Reduced motor power or torque
- Possible limp mode or vehicle shutdown
How to diagnose it
- Review freeze-frame and live data for sensor B and note when the signal becomes erratic, including whether the fault coincides with vibration or changing load.
- With the vehicle powered down under the manufacturer’s high-voltage safety procedure, inspect sensor B’s connector for incomplete seating, loose terminals, corrosion, or moisture.
- Inspect the accessible sensor B wiring and its ground reference for chafing, poor connections, or signs of movement-related damage.
- Use the manufacturer’s diagnostic procedure to monitor sensor B while checking the circuit connections for intermittent contact.
- Repair the identified connection, ground, or sensor fault, then verify that the reading stays stable during the specified checks.
Common fixes
- Fully seat and secure the sensor B connector.
- Clean or repair loose or corroded connector terminals.
- Repair damaged sensor B wiring or its poor ground reference.
- Replace sensor B if its output remains erratic with sound wiring and connections.
Can I keep driving?
Driving may be unreliable because a momentary signal loss can trigger reduced torque or limp mode. Avoid trips where a sudden power reduction would be hazardous, and stop safely if the warning or power loss occurs.
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.