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 a sensor in the car's battery is saying something is wrong. It's like when a toy's battery is too big or too small, and it doesn't fit right.
The P2E71 code indicates that the sensor measuring the thickness of the cells in the Hybrid/EV Battery Pack B is detecting a higher than normal reading.
The P2E71 code is triggered when the vehicle's Powertrain Control Module (PCM) or Battery Management System (BMS) detects a high voltage signal from the cell thickness sensor circuit of Battery Pack B. This could indicate an issue with the sensor itself, the wiring, or the battery cells.
• Check Engine Light is on
• Reduced battery performance
• Possible warning messages on the dashboard
• Faulty cell thickness sensor
• Damaged wiring or connectors
• Battery cell swelling or deformation
PCM: Powertrain Control Module
BMS: Battery Management System
• Scan the vehicle for additional codes
• Inspect the wiring and connectors of the cell thickness sensor
• Test the sensor for proper operation
• Replace the faulty cell thickness sensor
• Repair or replace damaged wiring or connectors
• Inspect and replace any damaged battery cells
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regular battery maintenance
• Ensure proper charging habits
• Avoid extreme temperature exposure
Sensor Issue
• Avoid long trips until the issue is resolved
• Monitor battery performance closely
Check with your vehicle manufacturer for battery warranty coverage.
This code is more common in older hybrid and electric vehicles as their batteries age.
Moderate – It should be addressed soon to prevent further battery damage.
Driving with a faulty battery sensor can lead to reduced vehicle performance and potential safety issues.
• Vehicle in 'On' position
• Battery at normal operating temperature
The cell thickness sensor is typically located within the battery pack, often requiring battery disassembly for access.
Q: Can I drive with this code?
A: It's not recommended to drive for long periods with this code, as it may affect battery performance.
Q: Will this code affect my car's performance?
A: Yes, it can lead to reduced battery efficiency and overall vehicle performance.
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