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 has detected a problem with the battery's voltage sensor. It's like when your remote control's battery is running low, and it doesn't work well.
The vehicle's control module has detected that the voltage in the battery sense circuit 'D' is lower than expected.
The P0B4C code indicates that the Powertrain Control Module (PCM) or Battery Energy Control Module (BECM) has detected a low voltage condition in the battery voltage sense circuit 'D'. This circuit is responsible for monitoring the voltage levels of the hybrid or electric vehicle's battery pack to ensure it is operating within the specified range.
• Check Engine Light is on
• Reduced fuel efficiency
• Decreased battery 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 wiring and connectors for damage or corrosion.
• Test the battery voltage sensor for proper operation.
• Replace the faulty battery voltage sensor.
• Repair or replace damaged wiring/connectors.
• Replace the Battery Energy Control Module if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regularly inspect battery connections.
• Ensure battery sensors are functioning correctly.
• Perform routine maintenance checks.
Sensor Issue
• Avoid driving the vehicle until the issue is resolved to prevent further damage.
• Consult with a professional mechanic for accurate diagnosis and repair.
Check if the vehicle's battery or electrical components are covered under warranty.
This code has been more common with the increasing use of hybrid and electric vehicles, as battery systems become more complex.
Moderate – It is important to address this issue soon to prevent potential battery damage.
Driving with a malfunctioning battery system can lead to reduced vehicle 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 or integrated into the Battery Energy Control Module.
Q: Can I drive with a P0B4C code?
A: It's not recommended to drive with this code as it can lead to further battery issues.
Q: How do I clear a P0B4C code?
A: The code can be cleared with an OBD-II scanner after the issue is resolved, but it may return if the problem persists.
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.