The supercharger does double-duty on this car, in addition to being used in the standard fashion as a supercharger it is also used as an air pump for the secondary air-injection system. There are a series of diverter-flaps and switchover valves that accomplish this task, a malfunction in any of these devices can cause the codes your mechanic reported.

In addition a weak O2 sensor or a plugged line in the air injection tubing has also been know to trigger this code.

I'd like to know a whole lot more about exactly what was done to determine the supercharger is at fault, there are a whole lot of other things that are more likely to cause this code (P0410 I think?)

Do a search for 'P0410 + C230' for more info.

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