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 reading the battery's voltage correctly. It's like when a video game controller keeps disconnecting and reconnecting, making it hard to play the game smoothly.
The vehicle's control module detects an issue with the voltage sensing circuit for the hybrid or electric vehicle battery. The signal is either intermittent or erratic.
The P0B99 code is triggered when the powertrain control module (PCM) or battery energy control module (BECM) detects an intermittent or erratic signal from the hybrid/EV battery voltage sense S circuit. This can affect the vehicle's ability to monitor and manage the battery's state of charge accurately.
• Check Engine Light illuminated
• Reduced fuel efficiency
• Possible reduced vehicle performance
• Faulty battery voltage sensor
• Damaged or corroded wiring/connectors
• Faulty battery energy control module (BECM)
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 wiring for damage.
• Check connectors for corrosion or looseness.
• Replace or repair faulty wiring/connectors.
• Replace the battery voltage sensor if defective.
• Replace the battery energy control module if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $500
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regularly inspect battery connections.
• Keep battery terminals clean.
• Ensure proper maintenance of the hybrid/EV system.
Sensor Issue
• Avoid high-speed driving until the issue is resolved.
• Have the vehicle inspected by a professional if unsure about the repair.
Check with the vehicle manufacturer for warranty coverage on hybrid/EV components.
This code has been reported in various hybrid and electric vehicles, often related to sensor or wiring issues.
Moderate – While the vehicle may still operate, it could lead to reduced performance or efficiency.
Driving with a malfunctioning hybrid/EV system can lead to reduced performance and efficiency. It is recommended to address the issue promptly.
• Vehicle at operating temperature
• Battery system under load
The battery voltage sensor is typically located near the hybrid/EV battery pack.
Q: Can I drive my car with a P0B99 code?
A: It's possible to drive, but you may experience reduced performance and efficiency. It's best to have it checked soon.
Q: Will this code affect my car's battery life?
A: If not addressed, it could lead to improper battery management, potentially affecting battery life.
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