Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's battery cooling pump is spinning too fast because it's not getting enough coolant, like a fan spinning in the air instead of water.
This code indicates that the coolant pump for the hybrid or electric vehicle's battery pack is running at a higher speed than normal, likely due to a lack of coolant in the system.
The P2B29 code is triggered when the control module detects that the battery pack coolant pump A is operating at an overspeed condition, which can occur when the pump is running dry. This means that the pump is not moving coolant as expected, potentially due to a lack of coolant or a blockage in the system.
• Warning light on the dashboard
• Overheating battery pack
• Reduced vehicle performance
• Low coolant level
• Blocked coolant lines
• Faulty coolant pump
Coolant: A fluid used to keep the engine and battery from overheating.
Battery Pack: A set of batteries that power an electric or hybrid vehicle.
• Check coolant level in the reservoir.
• Inspect coolant lines for blockages or leaks.
• Test the coolant pump for proper operation.
• Refill the coolant to the proper level.
• Clear any blockages in the coolant lines.
• Replace the coolant pump if faulty.
• Coolant refill kit
• Multimeter
• Wrench set
$100 - $500
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regularly check coolant levels.
• Perform routine maintenance on the cooling system.
• Inspect for leaks periodically.
Cooling System Issue
• Do not ignore the warning light; check the coolant level immediately.
• Avoid driving the vehicle until the issue is resolved to prevent damage.
Check with the vehicle manufacturer for warranty coverage on hybrid/EV components.
This code has become more common with the increase in hybrid and electric vehicles, as proper cooling is essential for battery longevity.
High – Immediate attention required to prevent battery damage.
Operating a vehicle with an overheating battery can be dangerous and may void warranties.
• Vehicle must be in a safe environment.
• Ensure the engine is off and the vehicle is cool before inspection.
The coolant pump is typically located near the battery pack, often in the rear of the vehicle.
Q: What happens if I ignore this code?
A: Ignoring this code can lead to battery damage and potential safety hazards.
Q: Can I fix this issue myself?
A: If you are comfortable with car maintenance, you can check the coolant level and lines, but a professional should handle pump replacement.
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