Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer thinks the temperature sensor for the electric motor's inverter is reading too low. It's like a thermometer that is saying it's colder than it actually is.
The P0AF4 code indicates that the voltage signal from the drive motor inverter temperature sensor B is lower than expected by the vehicle's powertrain control module (PCM).
The drive motor inverter temperature sensor B monitors the temperature of the inverter, which is a component that converts DC electricity to AC for the electric motor. A low circuit signal suggests that the sensor is reporting a temperature that is too low, potentially due to a wiring issue, sensor failure, or other electrical problem.
• Check Engine Light is on
• Reduced vehicle performance
• Possible overheating of the inverter
• Faulty drive motor inverter temperature sensor B
• Wiring issues such as shorts or open circuits
• Faulty PCM
Inverter: A device that converts DC electricity to AC electricity.
PCM: Powertrain Control Module, the car's main computer that controls engine and transmission functions.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors related to the temperature sensor B.
• Test the sensor for proper operation using a multimeter.
• Replace the drive motor inverter temperature sensor B if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regular maintenance checks
• Ensure proper cooling system operation
• Avoid overloading the vehicle's electrical system
Sensor Issue
• If the Check Engine Light comes on, have the vehicle inspected as soon as possible.
• Avoid driving the vehicle if you notice performance issues.
Check with your vehicle manufacturer for specific warranty coverage on emissions and hybrid components.
This code has been known to appear in hybrid and electric vehicles due to sensor or wiring issues.
Moderate – While the vehicle may still operate, ignoring this code can lead to more significant issues.
Driving with a malfunctioning inverter temperature sensor could lead to overheating and potential safety hazards.
• Engine must be running
• Vehicle should be at operating temperature
The drive motor inverter temperature sensor B is typically located near the inverter assembly in the engine compartment.
Q: What happens if I ignore this code?
A: Ignoring this code can lead to inverter overheating and reduced vehicle performance.
Q: Can I drive my car with this code?
A: It's possible to drive, but it's not recommended as it may lead to further damage.
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