Location
The temperature sensor downstream of air filter (B611) is located in the air intake hose between the air filter and ATL.
Shown on engine 471.9 |
B611 | Temperature sensor downstream of air filter |
W09.20-1004-06
Task
Over the temperature sensor downstream of air filter (B611) the engine management (MCM) control unit (A4) detects the temperature of the intake air on the compressor inlet of the ATL.
In combination with the current rotor speed and engine load condition, the engine management control unit (MCM) (A4 ) detects, among other things, whether the boost pressure regulator (Y636) must be actuated and the injection adapted in order to protect the exhaust gas turbocharger against too high thermal loads.
Structure
There is an NTC resistor inside the temperature sensor downstream of air filter (B611). NTC stands for "Negative Temperature Coefficient", which means that electrical resistance falls as temperature rises.
Function
The intake air blowing by at the temperature sensor downstream of air filter (B611) influences the temperature of the measuring elements inside the sensor according to their temperature and therefore the magnitude of the electrical resistance. The engine management control unit (MCM) (A4) derives the associated temperature from the electrical resistance.