Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with a sensor that measures how hot a part of the engine is. It's saying the temperature is reading too high.
The P2B91 code is triggered when the Engine Control Module (ECM) detects a high voltage signal from the turbocharger or supercharger B temperature sensor circuit, indicating a higher than expected temperature reading.
The turbocharger or supercharger B temperature sensor is responsible for monitoring the temperature of the air being compressed by the turbocharger or supercharger. A high circuit signal indicates that the sensor is reporting a temperature that is higher than the predetermined threshold set by the manufacturer. This could be due to a malfunctioning sensor, wiring issues, or actual overheating.
• Check Engine Light is on
• Possible reduction in engine performance
• Overheating warning light may be on
• Unusual engine noises
• Faulty turbocharger/supercharger B temperature sensor
• Wiring issues such as shorts or open circuits
• Connector problems
• Actual overheating of the turbocharger/supercharger
• Faulty ECM
Turbocharger: A device that increases an engine's efficiency and power output by forcing extra air into the combustion chamber.
Supercharger: A mechanically driven device that increases the pressure or density of air supplied to an internal combustion engine.
• Use an OBD-II scanner to confirm the P2B91 code.
• Inspect the turbocharger/supercharger B temperature sensor and its wiring for damage.
• Check the sensor connector for corrosion or loose connections.
• Test the sensor's resistance and compare it to manufacturer specifications.
• Replace the faulty temperature sensor.
• Repair or replace damaged wiring or connectors.
• Ensure the turbocharger/supercharger is not actually overheating.
• Replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Ford F-150
• Chevrolet Silverado
• Dodge Ram
• Regularly check and maintain the turbocharger system.
• Ensure proper engine cooling.
• Inspect sensors and wiring during routine maintenance.
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if you are not familiar with engine components.
Check with the vehicle manufacturer for warranty coverage on sensors and related components.
This code has been reported in vehicles with turbocharged or supercharged engines, often related to sensor failures or wiring issues.
Moderate – This issue should be addressed soon to prevent potential engine damage.
Driving with a malfunctioning temperature sensor can lead to engine damage. Ensure repairs are done by a qualified technician.
• Engine at operating temperature
• Under load conditions
The temperature sensor is typically located near the turbocharger or supercharger, often on the intake side.
Q: Can I drive with a P2B91 code?
A: It's not recommended to drive for extended periods with this code, as it could indicate overheating issues.
Q: How do I reset the Check Engine Light after repairs?
A: Use an OBD-II scanner to clear the code after fixing the issue.
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