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Charge air pressure sensor

Charge air pressure sensor



There are two metal coated ceramic discs mounted close to each other in the pressure sensor. The disc closest to the pressure connection is thinner and bends when exerted to pressure. This changes the capacity between the metal coatings on the discs in relation to the pressure. Integrated in the sensor is a circuit that converts the capacity to an analogue voltage. The pressure sensor is connected to the engine intake manifold and is supplied with 5V from control module pin 98 and is grounded from control module pin 87.

Depending on the pressure in the charge air pipe, the pressure sensor delivers a proportional voltage to control module pin 93.

The control module uses this information from the pressure sensor to:


- Protect the induction system from pulsed air.

- Protect the turbocharger from overspeeding.


At normal atmospheric pressure, 100 kPa, the pressure from the sensor is approx. 2.1 V.

Diagnostics


If the pressure sensor input is shorted to ground, DTC P0107 will be generated.

If the pressure sensor input is shorted to B+, DTC P0108 will be generated.

If the pressure value is implausible, DTC P0106 will be generated.


System reaction to a fault


The control module will continue to use a substitute value that is the same as the atmospheric pressure.

The following limitations will apply: Pedal position sensor adjustable to max 60%.

Turbo and EGR control disengaged.


PRE-RELEASE