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 electrical circuit that controls a pump used to cool the battery in a hybrid or electric vehicle. It's like a fan that helps keep your computer cool, but for the car's battery.
The P0E1A code indicates an issue with the control circuit for the second coolant pump in a hybrid or electric vehicle's battery cooling system. This could be due to an open circuit, meaning there is a break or disconnection in the wiring.
The P0E1A diagnostic trouble code is triggered when the vehicle's powertrain control module (PCM) detects a malfunction in the electrical circuit responsible for controlling the Hybrid/EV Battery Pack Coolant Pump B. This pump is crucial for maintaining optimal battery temperature by circulating coolant through the battery pack.
• Illuminated check engine light
• Overheating battery pack
• Reduced vehicle performance
• Faulty coolant pump B
• Open or shorted wiring in the control circuit
• Faulty PCM or control module
PCM: Powertrain Control Module
EV: Electric Vehicle
• Perform a visual inspection of the coolant pump and wiring.
• Use a multimeter to check for continuity in the control circuit.
• Test the functionality of the coolant pump.
• Repair or replace damaged wiring.
• Replace the faulty coolant pump.
• Reprogram or replace the PCM if necessary.
• Multimeter
• OBD-II scanner
• Basic hand tools
$200 - $800
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regular inspection of the coolant system
• Ensure proper coolant levels
• Routine maintenance checks
Control Circuit Issue
• Avoid driving the vehicle until repaired to prevent battery damage.
• Schedule a service appointment with a qualified technician.
Check vehicle warranty for coverage on hybrid/EV components.
This code has become more common with the increase in hybrid and electric vehicles, as battery cooling systems are critical for performance and longevity.
High – Failure to address this issue can lead to battery overheating and potential damage.
Driving with an overheated battery can be dangerous and may violate emissions regulations.
• Vehicle at operating temperature
• Battery under load conditions
The coolant pump is typically located near the battery pack, often in the rear of the vehicle.
Q: Can I drive my car with a P0E1A code?
A: It's not recommended, as it could lead to battery damage due to overheating.
Q: How do I know if my coolant pump is working?
A: You can listen for the pump's operation or use diagnostic tools to check its function.
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