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 your game controller's battery is low and the signal keeps cutting out.
The vehicle's control module is detecting an intermittent or erratic signal from the battery voltage sensing circuit.
The P0B85 code is triggered when the powertrain control module (PCM) or battery energy control module (BECM) detects an inconsistent or erratic voltage signal from the hybrid or electric vehicle's battery voltage sense circuit. This can affect the vehicle's ability to manage battery charging and discharging effectively.
• Check Engine Light is on
• Reduced fuel efficiency
• Possible loss of power or reduced performance
• Faulty battery voltage sensor
• Loose or corroded battery connections
• Damaged wiring or connectors 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 the wiring and connectors for damage or corrosion.
• Replace the faulty battery voltage sensor.
• Clean and secure battery connections.
• Repair or replace damaged wiring or connectors.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regularly inspect battery connections for corrosion.
• Ensure all battery connections are tight.
• Perform routine maintenance checks on the battery system.
Sensor Issue
• Avoid heavy acceleration until the issue is resolved.
• Schedule a service appointment with a qualified technician.
• Monitor battery performance and efficiency.
Repairs may be covered under the vehicle's hybrid or EV battery warranty.
This code has been associated with issues in hybrid and electric vehicles as they age, particularly in models with high mileage.
Moderate – While the vehicle may still operate, it's important to address the issue to prevent further problems.
Driving with a malfunctioning battery voltage sensor can lead to reduced performance and efficiency. It's advisable to have the vehicle inspected and repaired promptly.
• Vehicle in 'ON' position
• Battery fully charged
The battery voltage sensor is typically located near the hybrid or EV battery pack.
Q: Can I drive with a P0B85 code?
A: It's possible to drive with this code, but it's not recommended as it can lead to reduced performance and efficiency.
Q: How do I clear a P0B85 code?
A: After repairing the issue, use an OBD-II scanner to clear the code. If the problem persists, the code will return.
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