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 thinks one of the wires that checks the battery's power is showing a number that's too low to be true.
The vehicle's control module has detected an implausibly low voltage reading from the 'K' circuit in the hybrid or electric vehicle battery voltage sensing system.
The P1B86 code is triggered when the powertrain control module (PCM) or battery management system (BMS) detects an implausibly low voltage reading from the battery voltage sense 'K' circuit. This could indicate a problem with the circuit wiring, connectors, or the sensor itself.
• Check Engine Light is on
• Reduced fuel efficiency
• Possible reduced power or performance
• Faulty battery voltage sensor
• Damaged or corroded wiring or connectors
• Faulty battery management system (BMS)
PCM: Powertrain Control Module
BMS: Battery Management System
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the battery voltage sensor for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the faulty battery voltage sensor.
• Reprogram or replace the battery management system if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Chevrolet Volt
• Nissan Leaf
• Toyota Prius
• Regularly inspect battery connections and wiring.
• Keep the battery management system software updated.
• Ensure proper maintenance of the hybrid/EV battery system.
Sensor Issue
• Do not ignore the Check Engine Light.
• Seek professional diagnosis and repair.
• Avoid driving the vehicle aggressively until repaired.
Repairs may be covered under the vehicle's hybrid/EV battery warranty.
This code has been more prevalent in older hybrid and EV models as they age and their battery systems wear.
Moderate – Addressing this issue promptly can prevent further damage to the battery system.
Driving with a malfunctioning battery system can lead to reduced performance and efficiency. Ensure repairs are conducted by qualified personnel.
• Vehicle at operating temperature
• Battery fully charged
The battery voltage sensor is typically located within the battery pack or near the battery management system.
Q: Can I drive with a P1B86 code?
A: It's not recommended to drive for extended periods with this code, as it may lead to further damage.
Q: What happens if I ignore this code?
A: Ignoring this code could result in reduced vehicle performance and efficiency, and potentially more costly repairs.
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