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 has detected a problem with the sensor that checks how hot a part of the electric motor system is getting. It's like when a thermometer isn't working right and you can't tell if it's too hot or not.
The P1E21 code indicates that the temperature sensor for the drive motor 'B' inverter is not reading within the expected range, which could affect the electric motor's performance.
The drive motor 'B' inverter temperature sensor 'B' monitors the temperature of the inverter, which is crucial for managing the thermal conditions of the electric drive system. If the sensor's output is outside the expected range, it could indicate a sensor malfunction or an actual overheating condition.
• Check Engine Light is on
• Reduced performance of the electric motor
• Overheating warning
• Faulty temperature sensor
• Wiring issues such as shorts or open circuits
• Faulty inverter
Inverter: A device that converts DC electricity to AC electricity.
Sensor: A device that detects or measures a physical property and records, indicates, or otherwise responds to it.
• Use a diagnostic scanner to confirm the code
• Inspect the wiring and connectors for damage
• Test the temperature sensor for proper operation
• Replace the faulty temperature sensor
• Repair or replace damaged wiring
• Replace the inverter if necessary
• OBD-II scanner
• Multimeter
• Wrench set
$200 - $600
Moderate
• Chevrolet Volt
• Chevrolet Bolt EV
• Nissan Leaf
• Regular maintenance checks
• Ensure proper cooling system operation
• Avoid excessive load on the electric motor
Sensor Issue
• Do not ignore the Check Engine Light
• Avoid driving aggressively until the issue is resolved
Check with the vehicle manufacturer for warranty coverage on electric drive components.
This code has become more common with the increased use of electric and hybrid vehicles, highlighting the importance of thermal management in these systems.
Moderate – It should be addressed soon to prevent potential damage to the electric drive system.
Ignoring this issue could lead to reduced vehicle performance and potential safety hazards.
• Vehicle should be at operating temperature
• Test under normal driving conditions
The temperature sensor is located near the drive motor 'B' inverter, typically within the engine bay or electric drive unit.
Q: Can I drive my car with a P1E21 code?
A: It's best to have the issue checked out as soon as possible to avoid potential damage.
Q: What happens if I ignore this code?
A: Ignoring it could lead to overheating and damage to the electric drive system.
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