I think that's a sensor that's plugged in to the top of your intercooler, which tells the car how much boost is going in to the engine. Did the fault code say anything specific? I just ask because the description can sometimes indicate whether the sensor has become inaccurate or if the wiring could be to blame.
Depending on the above, I think you get to it by removing your front bumper, you could disconnect and reconnect it a few times to ensure that the connections are good.
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