Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This means there's a problem with the part of the car that helps keep the battery warm. It's like when you have a blanket to keep warm, but there's a hole in it, so it doesn't work right.
The code indicates that there is an issue with the control circuit for the heater that warms the battery pack coolant in a hybrid or electric vehicle.
The P0E12 code is set when the Powertrain Control Module (PCM) or Battery Energy Control Module detects an open or malfunction in the control circuit of the battery pack coolant heater. This heater is responsible for maintaining the battery temperature within optimal operating conditions, especially in cold environments.
• Check Engine Light illuminated
• Reduced battery performance
• Possible battery overheating or underheating
• Faulty battery pack coolant heater
• Open or shorted wiring in the heater circuit
• Poor electrical connection in the heater circuit
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the battery pack coolant heater for proper operation.
• Replace the battery pack coolant heater if faulty.
• Repair or replace damaged wiring or connectors.
• Clear the code and test drive the vehicle to ensure the issue is resolved.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $500
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regularly inspect wiring and connectors for damage.
• Ensure the cooling system is properly maintained.
• Avoid extreme temperatures when possible.
Control Circuit Issue
• Have the vehicle inspected by a professional if you notice any performance issues.
• Regular maintenance can help prevent this issue.
This issue may be covered under the vehicle's powertrain or emissions warranty. Check with your manufacturer.
This code has been more prevalent in colder climates where battery heating is more critical.
Moderate – While the vehicle can still operate, ignoring the issue may lead to reduced battery efficiency and potential long-term damage.
Driving with a malfunctioning battery heater can lead to reduced vehicle performance and efficiency. Addressing the issue promptly is recommended.
• Vehicle should be at operating temperature.
• Ensure the battery is charged.
The battery pack coolant heater is typically located near the battery pack, often in the rear of the vehicle.
Q: Can I drive with the P0E12 code?
A: You can drive with this code, but it's best to address it soon to avoid potential battery issues.
Q: What happens if I ignore this code?
A: Ignoring this code can lead to reduced battery efficiency and possible long-term damage.
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