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 pump that cools the battery in a hybrid or electric car is running without any coolant, which can make the battery too hot.
The P1B29 code is triggered when the vehicle's control module detects that the battery pack coolant pump is running without sufficient coolant, which can lead to overheating.
The hybrid or electric vehicle's battery pack relies on a coolant system to maintain optimal operating temperatures. The coolant pump circulates the coolant, and if it runs dry, it can cause the battery to overheat, potentially leading to reduced performance or damage. This code indicates a malfunction in the coolant pump's operation, specifically that it is running without coolant.
• Warning light on dashboard
• Reduced battery performance
• Overheating of the battery pack
• Unusual noises from the coolant pump
• Low coolant level
• Coolant leak
• Faulty coolant pump
• Blocked coolant lines
• Faulty sensor or wiring
Coolant: A fluid used to transfer heat away from the engine or battery.
Battery Pack: A set of batteries used to power an electric or hybrid vehicle.
• Check the coolant level in the battery cooling system.
• Inspect for any visible coolant leaks.
• Test the coolant pump for proper operation.
• Check the coolant lines for blockages.
• Inspect wiring and sensors related to the coolant pump.
• Refill the coolant to the proper level.
• Repair any leaks in the coolant system.
• Replace the faulty coolant pump if necessary.
• Clear any blockages in the coolant lines.
• Repair or replace faulty sensors or wiring.
• Coolant refill kit
• Leak detection kit
• Multimeter
• Wrench set
• Diagnostic scanner
$200 - $600
Moderate
• Chevrolet Volt
• Toyota Prius
• Nissan Leaf
• Regularly check coolant levels.
• Inspect for leaks periodically.
• Maintain the cooling system as per the manufacturer's schedule.
Cooling System Issue
• Do not ignore the warning light; address the issue promptly.
• Monitor the vehicle's temperature gauge regularly.
• Schedule regular maintenance checks for the cooling system.
Check with the vehicle manufacturer for warranty coverage on hybrid or EV components.
This code has been more common as hybrid and electric vehicles have become more prevalent, highlighting the importance of battery cooling systems.
High – Overheating can lead to battery damage or reduced performance.
Ignoring this code can lead to safety risks due to potential battery overheating. Always address promptly.
• Vehicle must be in operation.
• Coolant system must be pressurized.
The battery pack coolant pump is typically located near the battery pack, often in the rear of the vehicle.
Q: Can I drive with a P1B29 code?
A: It's not recommended to drive with this code active as it can lead to battery overheating and damage.
Q: How often should I check the coolant level?
A: Check the coolant level at least once every few months or as recommended by the vehicle manufacturer.
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