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Temperature Sensor Upstream Of Exhaust Gas Turbocharger, Basic Function - GF09.40-P-2000A

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Engine All (4xWD, CAR) 

G16048329Courtesy of MERCEDES-BENZ USA

Sample illustration, temperature sensor upstream of exhaust gas turbocharger 

Overview 

This document contains information on:

General 

The temperature sensor upstream of the exhaust gas turbocharger is located on the combustion engine upstream of the exhaust gas turbocharger.

The combustion engine control unit determines the temperature of the intake air at the compressor inlet of the exhaust gas turbocharger via the temperature sensor upstream of the exhaust gas turbocharger

In combination with the current compressor wheel rotational speed and the load condition of the combustion engine, the combustion engine control unit detects whether the boost pressure control flap actuator is being actuated.

The injection is adapted accordingly in order to protect the exhaust gas turbocharger against excessive thermal loads.

Function 

Depending on its temperature, the intake air flowing past the temperature sensor upstream of the exhaust gas turbocharger influences the temperature of the measuring element inside the sensor and thus the amount of electrical resistance. The combustion engine control unit derives the associated temperature from the electrical resistance.

There is an NTC resistor in the temperature sensor upstream of the exhaust gas turbocharger. NTC stands for "Negative Temperature Coefficient", which means that electrical resistance falls as temperature rises.