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 part that measures the battery's power. It's like a battery checker that isn't working right.
The vehicle's control module has detected a low voltage condition in the voltage sense circuit 'C' of the hybrid or electric vehicle battery pack.
The P0B1B code indicates that the Battery Energy Control Module (BECM) has found an issue with the voltage sense circuit 'C' in the hybrid or electric vehicle's battery pack. This circuit is responsible for monitoring the voltage levels of the battery cells to ensure they are within the proper operating range. A low voltage reading can suggest a wiring problem, a faulty sensor, or an issue with the battery pack itself.
• Check Engine Light is on
• Reduced fuel efficiency
• Possible reduced vehicle performance
• Faulty battery voltage sensor
• Damaged or corroded wiring/connectors
• Faulty Battery Energy Control Module (BECM)
BECM: Battery Energy Control Module
OBD-II: On-Board Diagnostics, Second Generation
• 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.
• Replace or repair damaged wiring/connectors.
• Replace the faulty battery voltage sensor.
• Replace or reprogram the Battery Energy Control Module if necessary.
• OBD-II scanner
• Digital multimeter
• Basic hand tools
$200 - $800
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regularly inspect battery connections.
• Ensure battery sensors are functioning properly.
• Perform routine maintenance on hybrid/EV systems.
Sensor Issue
• Avoid driving the vehicle until the issue is diagnosed.
• Consult a professional mechanic for accurate diagnosis.
• Consider checking for recalls related to the battery system.
Check with the vehicle manufacturer for warranty coverage on hybrid/EV components.
This code has been commonly reported in hybrid and electric vehicles as they age, often due to wear and tear on battery components.
Moderate – It's important to address this issue soon to prevent further damage to the battery system.
Driving with a malfunctioning battery system can lead to reduced vehicle performance and efficiency. Always ensure your vehicle is safe to operate.
• Vehicle at operating temperature
• Battery pack fully charged
The voltage sense circuit is typically located within the battery pack or near the Battery Energy Control Module.
Q: Can I drive my car with this code?
A: It's not recommended to drive with this code active, as it can lead to further issues with your vehicle's battery system.
Q: How can I prevent this issue?
A: Regular maintenance and inspections of the battery system can help prevent this issue.
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