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 there's a problem with the way it measures the battery's power. It's like when a video game says your score is way too high because something went wrong.
The vehicle's control module has detected an unusually high voltage reading from the 'K' circuit of the hybrid or electric vehicle battery voltage sensing system.
The P1B87 code is triggered when the powertrain control module (PCM) or battery energy control module (BECM) detects an implausibly high voltage reading from the 'K' circuit of the battery voltage sensing system. This could be due to a fault in the circuit, sensor, or the control module itself.
• Check Engine Light illuminated
• Reduced fuel efficiency
• Limited vehicle performance
• Faulty battery voltage sensor
• Wiring issues in the voltage sense circuit
• Defective battery energy control module
PCM: Powertrain Control Module
BECM: Battery Energy Control Module
• Use an OBD-II scanner to confirm the code.
• Inspect the battery voltage sensor and related wiring.
• Test the battery energy control module for faults.
• Replace the faulty battery voltage sensor.
• Repair or replace damaged wiring in the circuit.
• Replace the battery energy control module if necessary.
• OBD-II scanner
• Multimeter
• Wiring repair kit
$200 - $800
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regular maintenance checks on the battery system.
• Ensure all software updates are applied.
• Inspect wiring for wear and tear periodically.
Sensor Issue
• Avoid driving the vehicle until the issue is resolved to prevent further damage.
• Consult a professional mechanic for an accurate diagnosis.
Check with the vehicle manufacturer for specific warranty coverage related to hybrid/EV components.
This code has become more common as hybrid and electric vehicles have increased in popularity, highlighting the need for precise battery management systems.
High – Addressing this issue promptly is important to prevent potential battery damage or failure.
Operating a vehicle with a faulty battery voltage sensor can lead to reduced performance and potential safety hazards.
• Vehicle at operating temperature
• Battery fully charged
The battery voltage sensor is typically located near the vehicle's battery pack, often in the rear of the vehicle.
Q: Can I drive my car with a P1B87 code?
A: It's not recommended to drive with this code active, as it may lead to further damage or reduced performance.
Q: How can I prevent this code from appearing?
A: Regular maintenance and checks on the battery system and updating the vehicle's software can help prevent this issue.
High-End · Full-system diagnostics
A full-system bidirectional platform aimed at advanced DIY users and professional diagnostic workflows.
Network faults often require full-system access instead of a generic code reader alone.
View on Amazon
Universal · Digital multimeter
A solid entry-level multimeter for voltage, continuity, resistance, and basic electrical troubleshooting.
Helpful for checking voltage drops, grounds, and basic circuit health when modules are not communicating.
View on Amazon
Universal · Wire connectors and repair kit
Useful when diagnosis points toward damaged wiring, corroded terminals, or connector repairs.
Useful if diagnosis points toward damaged connectors, wiring, or terminal repairs.
View on AmazonThese are optional diagnostic tools, not guaranteed fixes. As an Amazon Associate I earn from qualifying purchases.