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 thinks there's a problem with the part that helps keep the battery cool. It's like if a fan in your computer stopped working, and the computer got worried that it might get too hot.
The P0E1B code is triggered when the control circuit for the second coolant pump in the hybrid or electric vehicle's battery pack is detected to have low voltage.
The P0E1B code indicates an issue in the control circuit for the secondary coolant pump responsible for cooling the hybrid or electric vehicle's battery pack. This circuit is monitored by the vehicle's powertrain control module (PCM), and a low voltage reading suggests a potential wiring issue, faulty pump, or control module problem.
• Check engine light on
• Reduced battery performance
• Overheating of the battery pack
• Faulty coolant pump B
• Wiring issues in the control circuit
• Faulty powertrain control module (PCM)
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics II
• Use a scan tool to confirm the code and check for other codes.
• Inspect the wiring and connections to the coolant pump B.
• Test the coolant pump B for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the faulty coolant pump B.
• Replace or reprogram the PCM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $600
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regular maintenance of the cooling system
• Ensure proper coolant levels
• Inspect electrical connections periodically
Electrical Circuit Issue
• Avoid driving aggressively until the issue is resolved.
• Monitor battery temperature if possible.
Check with your vehicle manufacturer; hybrid components may have extended warranties.
This code has been more common in older hybrid models as they age and components wear out.
Moderate – It should be addressed soon to prevent battery overheating.
Ignoring this issue can lead to reduced vehicle performance and potential battery damage.
• Vehicle in 'Ready' mode
• Battery at normal operating temperature
The coolant pump B is typically located near the battery pack, often at the rear of the vehicle.
Q: Can I drive my car with this code?
A: It's best to get it checked soon to avoid potential battery damage.
Q: How do I reset the check engine light?
A: Fix the issue and use an OBD-II scanner to clear the code.
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