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 part of the battery that checks how much electricity is in it. It's like a battery monitor not working right.
The P0B20 code is triggered when the voltage sense circuit for the hybrid or electric vehicle's battery pack is reading lower than expected. This could indicate a problem with the wiring, connectors, or the battery management system.
The voltage sense circuit is responsible for monitoring the voltage levels of the battery pack in a hybrid or electric vehicle. A 'Circuit Low' condition indicates that the voltage reading is below the threshold set by the manufacturer, which could be due to a fault in the circuit, such as a short to ground or an open circuit.
• Check Engine Light is on
• Reduced fuel efficiency
• Limited power or performance
• Faulty battery voltage sensor
• Damaged or corroded wiring/connectors
• Faulty battery management system
OBD-II: On-Board Diagnostics, a standardized system for self-diagnostics in vehicles.
Battery Management System: A system that manages the battery pack's performance, safety, and charging.
• Use an OBD-II scanner to confirm the code
• Inspect the battery voltage sensor and its wiring
• Check the battery management system for faults
• Replace the faulty battery voltage sensor
• Repair or replace damaged wiring/connectors
• Reprogram or replace the battery management system
• OBD-II scanner
• Multimeter
• Wiring repair tools
$200 - $800
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regular maintenance checks
• Keep battery terminals clean
• Avoid deep discharging of the battery
Sensor Issue
• Do not ignore the Check Engine Light
• Have the vehicle inspected by a professional
• Avoid driving long distances until repaired
Check with the vehicle manufacturer for warranty coverage on hybrid/EV components.
This code has become more common with the rise of hybrid and electric vehicles, as battery management systems are critical for their operation.
Moderate – While the vehicle may still operate, ignoring this issue could lead to reduced performance or battery damage.
Driving with a malfunctioning battery system could lead to performance issues and is not recommended.
• Vehicle in READY mode
• Battery pack connected
The battery voltage sensor is typically located within the battery pack or near the battery management system.
Q: Can I drive my car with this code?
A: It's not recommended as it may lead to reduced performance or battery damage.
Q: How can I prevent this issue?
A: Regular maintenance and keeping the battery system clean can help prevent this issue.
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