Atmospheric pressure sensor (539), T8
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Atmospheric pressure sensor (539), T8
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Atmospheric pressure sensor (539)
The atmospheric pressure sensor informs the control module of the current atmospheric pressure. This is used to calculate smoke limitation. The higher the car is above sea level, the less oxygen there is in the air. The fuel supply must therefore be reduced. Atmospheric pressure also affects turbo pressure, which must be reduced at high altitudes so that the turbocharger does not overrev.
The pressure sensor is a piezoresistive sensor with its own electronics for signal amplification and temperature compensation.
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Pin No.
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Signal type
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Description
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1
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Power supply, 5 V
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Connected to ECM pin 42(A).
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2
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Ground
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Connected to ECM pin 30(A).
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3
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Signal
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Connected to ECM pin 8(A).
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The electronics in the sensor are semiconductive and are mounted on a chip that bends with changes in air pressure, thus allowing more or less voltage to pass depending on the outside air pressure.
