C240 (2002)

Hi I have this car for about 2.5 yrs now. I recently moved to a townhouse which has a covered parking , earlier I used to park on street in open.

Now in garage if windows are down and I put the key in the ignition, (there are two clicks in key turn, one before start, next to start the car)

The moment I go to 1st click .. car makes a humming sound like some motor just started .... ghuuuuuuuuuuuuuuuu ... quite noticably load in a closed garage. I dont if it is normal or I started noticing it now coz of closed garage. Now ifI do it outside on street, I can hear it probably coz I am trying to hear it.

Is it normal ? Does anyone have the same problem ? Or did I lost another 1000 $ ?


Please help