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 sensors checking the battery voltage is reading too high. It's like a thermometer saying it's really hot when it might not be.
The P0B66 code is triggered when the voltage sensed by the battery voltage sensor is higher than the expected range.
The P0B66 code indicates that the Hybrid/EV Battery Voltage Sense I Circuit is reporting a voltage level that is higher than the manufacturer's specified range. This could be due to a fault in the sensor, wiring issues, or a problem with the battery itself.
• Check Engine Light is on
• Reduced fuel efficiency
• Possible reduced performance of the hybrid/EV system
• Faulty battery voltage sensor
• Wiring issues or poor connection in the voltage sense circuit
• Faulty battery management system
OBD-II: On-Board Diagnostics, a standardized system in vehicles for self-diagnosing and reporting.
Voltage Sensor: A device that measures the voltage level of a battery or electrical system.
• Use an OBD-II scanner to confirm the code.
• Inspect the battery voltage sensor and its wiring for damage or disconnection.
• Test the battery management system for faults.
• Replace the faulty battery voltage sensor.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the battery management system if necessary.
• OBD-II scanner
• Multimeter
• Wire repair tools
$200 - $500
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regular maintenance checks on the hybrid/EV battery system.
• Ensure all electrical connections are secure and clean.
• Use the vehicle within recommended parameters to avoid overloading the system.
Sensor Issue
• If the Check Engine Light is on, have the vehicle inspected by a professional.
• Avoid driving the vehicle aggressively until the issue is resolved.
Check with your vehicle manufacturer for specific warranty coverage on hybrid/EV components.
This code has been more common as hybrid and EV technology becomes more prevalent in vehicles.
Moderate – It should be addressed soon to prevent potential damage to the battery system.
Driving with a malfunctioning battery system can lead to reduced vehicle performance and efficiency.
• Vehicle in ready mode
• Battery system under load
The battery voltage sensor is typically located near or integrated with the hybrid/EV battery pack.
Q: Can I drive with a P0B66 code?
A: It's possible to drive short distances, but it's recommended to get it checked soon to avoid further issues.
Q: What happens if I ignore the P0B66 code?
A: Ignoring the code could lead to decreased vehicle performance and potential damage to the battery system.
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