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 the battery is showing a voltage that's too high and doesn't make sense. It's like your phone saying it's 200% charged, which isn't possible.
The vehicle's control module detects an unusually high voltage reading from the Hybrid/EV battery voltage sense 'L' circuit.
The P1B89 code is triggered when the powertrain control module (PCM) or battery management system (BMS) receives a signal from the voltage sense 'L' circuit that is outside the expected range, indicating a potentially faulty high voltage reading. This can be due to a sensor malfunction, wiring issues, or a problem within the battery itself.
• Check engine light is on
• Reduced fuel efficiency
• Possible reduced vehicle performance
• Faulty voltage sensor
• Damaged or corroded wiring/connectors
• Defective battery management system
PCM: Powertrain Control Module
BMS: Battery Management System
• Verify the code with an OBD-II scanner
• Inspect wiring and connectors for damage or corrosion
• Test the voltage sensor and battery management system
• Replace faulty voltage sensor
• Repair or replace damaged wiring/connectors
• Reprogram or replace battery management system if necessary
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $600
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regularly inspect battery connections
• Ensure proper maintenance of hybrid/EV systems
• Avoid overcharging the battery
Sensor Issue
• Do not ignore the check engine light; seek professional diagnosis.
• Avoid driving long distances until the issue is resolved.
Check with your vehicle manufacturer; hybrid/EV components may have extended warranties.
This code has been reported more frequently as hybrid and electric vehicles become more common.
Moderate – Addressing this issue promptly can prevent further damage to the vehicle's electrical system.
Driving with a malfunctioning hybrid/EV system can lead to safety issues and reduced vehicle performance.
• Vehicle in 'Ready' mode
• Battery at normal operating temperature
The voltage sensor is typically located within or near the hybrid/EV battery pack.
Q: Can I drive my car with a P1B89 code?
A: It's not recommended to drive long distances. Get the issue diagnosed and repaired as soon as possible.
Q: Will this code affect my car's performance?
A: Yes, it can lead to reduced performance and efficiency, as well as potential safety issues.
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