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 found a problem when checking the battery's voltage after the car was turned off. It's like when you check your flashlight's batteries to make sure they still have power.
The vehicle's control module has detected an issue with the voltage sensing circuits of the hybrid or electric vehicle battery during a diagnostic check that occurs after the vehicle is turned off.
The P1B02 code is set when the hybrid or electric vehicle's control module identifies a fault in the battery voltage sensing circuits during an afterrunning diagnostic test. This test is performed to ensure that the battery's voltage levels are within the expected range even after the vehicle is turned off, ensuring the battery's health and performance.
• Check engine light is on
• Reduced battery performance
• Vehicle may not start or run properly
• Faulty battery voltage sensor
• Damaged wiring or connectors in the voltage sensing circuit
• Malfunctioning control module
OBD-II: On-Board Diagnostics, a standardized system for self-diagnostics and reporting in vehicles.
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 related wiring for damage.
• Check the control module for faults.
• Replace the faulty battery voltage sensor.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the control module if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regularly check and maintain battery connections.
• Perform routine diagnostic checks.
• Ensure the vehicle's software is up to date.
Sensor Issue
• Do not ignore the check engine light.
• Consult a professional mechanic if unsure.
• Regular maintenance can prevent such issues.
Check with the vehicle manufacturer for warranty coverage on hybrid/EV components.
This code has become more common with the increase in hybrid and electric vehicles, highlighting the importance of battery health diagnostics.
Moderate – It is important to address this issue to maintain battery health and vehicle performance.
Ignoring this code can lead to reduced efficiency and potential safety issues. Always ensure your vehicle is in safe operating condition.
• Vehicle must be turned off.
• Battery must be at a normal operating temperature.
The battery voltage sensor is typically located near or integrated with the vehicle's battery pack.
Q: What happens if I ignore this code?
A: Ignoring this code can lead to decreased battery performance and potential vehicle starting issues.
Q: Can I drive my car with this code?
A: While the car may still be drivable, it's best to have it checked to avoid further issues.
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