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 is having trouble getting a steady reading from a part of the battery that helps it know how much power is left. It's like when your game controller's battery meter keeps jumping around and you can't tell if it's full or almost empty.
The P0B71 code indicates an issue with the voltage sensing circuit for the hybrid or electric vehicle battery, specifically circuit K, where the readings are inconsistent or erratic.
The P0B71 code is triggered when the Powertrain Control Module (PCM) or Battery Energy Control Module (BECM) detects an intermittent or erratic voltage signal from the hybrid/EV battery voltage sense circuit K. This can affect the vehicle's ability to accurately monitor and manage the battery's state of charge.
• Check engine light is on
• Reduced fuel efficiency
• Possible battery charging issues
• Faulty battery voltage sensor
• Loose or corroded electrical connections
• Damaged or frayed wiring in the voltage sense circuit
PCM: Powertrain Control Module
BECM: Battery Energy Control Module
• Use an OBD-II scanner to confirm the code
• Inspect the battery voltage sensor and its connections
• Check wiring for damage or corrosion
• Replace the faulty battery voltage sensor
• Repair or replace damaged wiring
• Clean and secure electrical connections
• OBD-II scanner
• Multimeter
• Wire repair tools
$100 - $500
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regularly inspect battery connections
• Ensure proper maintenance of the battery system
• Avoid exposure to extreme temperatures
Sensor Issue
• Have the vehicle inspected by a professional
• Avoid long trips until the issue is resolved
Battery and related components may be covered under the vehicle's hybrid/EV warranty.
This code has been associated with issues in hybrid and electric vehicles as they age, particularly in models with high mileage.
Moderate – It is important to address this issue soon to avoid potential battery management problems.
Driving with a faulty battery sensor can lead to unexpected vehicle behavior. It is advised to have the issue diagnosed and repaired promptly.
• Vehicle in 'Ready' mode
• Battery at normal operating temperature
The battery voltage sensor is typically located near the hybrid/EV battery pack, often within the battery management system.
Q: Can I drive my car with this code?
A: It's not recommended to drive for long periods with this code, as it may lead to battery management issues.
Q: Will this code affect my car's performance?
A: Yes, it can affect fuel efficiency and the vehicle's ability to manage the battery effectively.
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