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Atmospheric pressure sensor

Atmospheric pressure sensor



The atmospheric pressure sensor, which is located in the engine bay on the bulkhead by connector H42-5, informs the control module of the current atmospheric pressure. Atmospheric pressure is used to calculate smoke limitation. The greater the car's altitude, the less oxygen there is in the air. The fuel supply must therefore be reduced. Atmospheric pressure also controls the boost pressure, which must be reduced at high altitudes to prevent the turbocharger from overrevving.

Connections on the atmospheric pressure sensor:


1. Power supply: Pin A on the sensor from pin 31 on the engine control module.

2. Sensor ground: Pin B on the sensor from pin 8 on the engine control module.

3. Signal, atmospheric pressure: Pin C on the sensor to pin 44 on the engine control module.


The pressure sensor is a piezoresistive sensor with its own electronics for signal amplification and temperature compensation. The electronics are all semi-conductor type integrated on a chip, which bends due to changes in pressure and in this way allows more or less current to pass.

Diagnostics

If a fault arises in the absolute pressure sensor circuit, one of the following DTCs can be generated:

P1106 Absolute pressure sensor, intake manifold. Unfeasibility atmospheric pressure.

P1107 Atmospheric pressure sensor. Open circuit / Short to Ground.

P1108 Atmospheric pressure sensor. Short to B+.

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