Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the part of the car that helps keep the big battery warm. It's like when your blanket has a hole and can't keep you warm at night.
The P0E16 code indicates that the control circuit for the secondary coolant heater in a hybrid or electric vehicle's battery pack is open or not functioning properly.
The Hybrid/EV Battery Pack Coolant Heater B is responsible for maintaining the optimal temperature of the battery pack by heating the coolant. An open circuit or malfunction in this control circuit can lead to inadequate heating, affecting battery performance and efficiency.
• Check engine light illuminated
• Reduced battery performance
• Increased battery temperature
• Vehicle may not start in cold conditions
• Faulty coolant heater
• Damaged wiring or connectors
• Blown fuse
• Faulty control module
Coolant: A fluid used to regulate temperature in engines and battery packs.
Circuit: A path for electrical current to flow.
• Check for any blown fuses related to the coolant heater circuit.
• Inspect wiring and connectors for damage or corrosion.
• Test the coolant heater for proper operation.
• Use a scan tool to check for related codes.
• Replace any blown fuses.
• Repair or replace damaged wiring or connectors.
• Replace the faulty coolant heater.
• Reprogram or replace the control module if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$150 - $500
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regularly inspect wiring and connectors for damage.
• Ensure coolant levels are maintained.
• Schedule regular maintenance checks.
Sensor Issue
• Avoid driving in extreme cold until repaired.
• Schedule a service appointment promptly.
Check with the manufacturer for specific warranty coverage on hybrid components.
This code has become more common as hybrid and electric vehicles have increased in popularity, highlighting the importance of battery temperature management.
Moderate – It should be addressed soon to prevent battery damage.
Driving with this issue may lead to reduced vehicle performance and efficiency. It is advisable to repair it promptly.
• Vehicle in a cold environment
• Battery pack under load
The coolant heater is typically located near the battery pack, often under the vehicle or in the trunk area.
Q: Can I drive with a P0E16 code?
A: It's possible, but not recommended, as it may affect battery performance and efficiency.
Q: How do I reset the P0E16 code?
A: After repairs, you can use an OBD-II scanner to clear the code. However, if the issue persists, the code will return.
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