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 that the voltage in one part of the hybrid or electric vehicle's battery is lower than it should be. It's like when a flashlight battery is running out of power and the light gets dim.
The vehicle's control module monitors the voltage levels of the hybrid/EV battery pack. If it detects that the voltage in a specific section, labeled as 'Battery B', is lower than expected, it triggers this code.
The P0B29 code is set when the Battery Management System (BMS) detects that the voltage of the hybrid or electric vehicle's battery section 'B' is below the manufacturer's specified threshold. This could indicate a problem with the battery cells, wiring, or the BMS itself.
• Reduced vehicle performance
• Warning light on the dashboard
• Possible inability to start the vehicle
• Faulty battery cell in section B
• Poor electrical connections or corroded terminals
• Malfunctioning Battery Management System (BMS)
BMS: Battery Management System - a system that monitors and manages the performance of a battery.
Voltage: The difference in electric potential between two points, measured in volts.
• Check for any other related codes
• Inspect battery connections and terminals for corrosion
• Test the voltage of the battery cells in section B
• Clean and secure battery connections
• Replace faulty battery cells
• Repair or replace the Battery Management System (BMS)
• Multimeter
• Battery terminal cleaner
• Diagnostic scan tool
$500 - $2000
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regularly inspect battery connections
• Perform routine battery maintenance
• Ensure proper charging habits
Battery Performance Issue
• Avoid driving the vehicle until the issue is resolved to prevent further damage.
• Consult a professional mechanic for accurate diagnosis and repair.
Battery components may be covered under the vehicle's hybrid/EV warranty, typically lasting 8 years or 100,000 miles.
This code has become more common as hybrid and electric vehicles age and their batteries degrade over time.
High – This issue can lead to reduced vehicle performance and potential safety risks.
Driving with a faulty battery can lead to unexpected vehicle behavior. It is recommended to address this issue promptly.
• Vehicle must be on and in ready mode
• Battery should be under load for accurate testing
The hybrid/EV battery pack is typically located under the rear seats or in the trunk area.
Q: Can I drive my car with a P0B29 code?
A: It's not recommended to drive with this code active, as it can lead to further damage and reduced performance.
Q: How do I know if my battery needs replacement?
A: If the battery voltage is consistently low and other repairs don't resolve the issue, it may need replacement.
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