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 is having trouble reading the temperature of one of the battery sensors. It's like when a thermometer stops working and you can't tell how hot or cold it is.
The vehicle's control module has detected an open circuit in the Hybrid/EV battery temperature sensor 'E', which means it can't get a proper temperature reading.
The P1EF6 code indicates that the powertrain control module (PCM) or battery energy control module (BECM) has detected a fault in the circuit of the Hybrid/EV battery temperature sensor 'E'. This could be due to a broken wire, a faulty sensor, or a poor connection, resulting in an open circuit condition.
• Check Engine Light is on
• Reduced fuel efficiency
• Possible reduced power output
• Faulty battery temperature sensor 'E'
• Open or shorted wiring in the sensor circuit
• Poor electrical connection at the sensor
PCM: Powertrain Control Module
BECM: Battery Energy Control Module
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to the battery temperature sensor 'E'.
• Test the sensor for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the faulty battery temperature sensor 'E'.
• Clear the code and test drive the vehicle to ensure the issue is resolved.
• OBD-II scanner
• Multimeter
• Basic hand tools
$100 - $300
Moderate
• Chevrolet Volt
• Toyota Prius
• Nissan Leaf
• Regularly inspect battery connections and wiring.
• Ensure proper maintenance of the hybrid/EV battery system.
• Avoid exposing the vehicle to extreme temperatures.
Sensor Issue
• Have the vehicle inspected by a professional if the Check Engine Light is on.
• Avoid driving the vehicle aggressively until the issue is resolved.
Repairs may be covered under the vehicle's powertrain or emissions warranty.
This code has become more common with the increased use of hybrid and electric vehicles, as these systems rely heavily on accurate temperature monitoring for battery management.
Moderate – It's important to address this issue to prevent potential battery damage.
Ignoring this code may lead to reduced vehicle performance and potential damage to the battery system.
• Ensure the vehicle is in a safe location.
• The vehicle should be at normal operating temperature.
The battery temperature sensor is typically located within or near the hybrid/EV battery pack.
Q: Can I drive my car with a P1EF6 code?
A: It's possible to drive, but it's not recommended as it may lead to further issues with the battery system.
Q: How do I know if my battery temperature sensor is faulty?
A: A diagnostic scan tool can confirm if the sensor is faulty by reading the error code and checking sensor data.
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