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 a sensor in the car that checks the temperature of a part that helps the car's electric motor work is seeing a temperature that's too low.
The P1B66 code indicates that the temperature reading from the Drive Motor Inverter Temperature Sensor 'C' is lower than expected, which could mean the sensor is malfunctioning or the actual temperature is too low.
The Drive Motor Inverter Temperature Sensor 'C' monitors the temperature of the inverter, which is crucial for the efficient operation of the electric drive motor. If the sensor reads a temperature lower than the acceptable range, it triggers the P1B66 code. This could be due to a sensor fault, wiring issues, or an actual low temperature condition.
• Check Engine Light is on
• Reduced vehicle performance
• Potential overheating warning
• Faulty temperature sensor
• Wiring or connection issues
• Actual low temperature condition
Inverter: A device that converts direct current (DC) to alternating current (AC).
Temperature Sensor: A device that measures temperature and converts it into a signal.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to the temperature sensor.
• Test the sensor for proper operation.
• Replace the faulty temperature sensor.
• Repair or replace damaged wiring or connectors.
• Ensure the cooling system is functioning properly.
• OBD-II scanner
• Multimeter
• Wrench set
$100 - $300
Moderate
• Chevrolet Volt
• Nissan Leaf
• Toyota Prius
• Regular maintenance of the cooling system
• Periodic inspection of electrical connections
• Use of manufacturer-recommended parts
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if unsure.
• Regularly check for any unusual vehicle behavior.
Check with the vehicle manufacturer for specific warranty coverage on sensors and electrical components.
This code has been reported in hybrid and electric vehicles where inverter temperature monitoring is critical.
Moderate – It should be addressed soon to prevent potential damage to the inverter system.
Driving with a malfunctioning temperature sensor can lead to overheating and potential safety risks.
• Engine at normal operating temperature
• All electrical connections secure
The Drive Motor Inverter Temperature Sensor 'C' is typically located near the inverter assembly, which is part of the electric drive system.
Q: What happens if I ignore this code?
A: Ignoring this code can lead to reduced vehicle performance and potential damage to the inverter system.
Q: Can I drive my car with this code?
A: It's not recommended to drive for extended periods with this code active, as it may cause further issues.
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