moyamin

Hello all,

On our 2015 C300 there is a whistling / whining noise very low pitch when we turn it off for a few seconds. Any idea as to what it might be related to? Is it normal?

Thanks.

DerekACS

Does your car have the full LED lighting system ? If so, it could be the cooling fans.

moyamin

Yes, full LED. That makes sense.

Thank you.

kowyzg0moo

This could also definitely be caused by the activation of the parking break which is automatic on any W205 purchased early-2015 add later. Earlier ones do not have the firmware to auto-engage.

moyamin

Thanks. We indeed purchased the car in mid 2015. However, the high pitch sound lasts longer (about a full minute after engine shut off) than required for auto parking brake activation.

Mohammad

7Fd4epzQ

Do you have the Luxury Style? If so, it may be the front grill opening/closing.

ManiacGT

Let's face it, it could be bloody anything... I say unless it's accompanied by smoke or flames then don't worry. Modern cars makes all sorts of weird noises.

kowyzg0moo

Seconded on this. Got my mom a C300 Luxury and about a minute or so after, the grill will close (giving enough time to cool down).

Aladdin2016

It's possible it could be the Hardrive for the navigation/music register?

I have a sound from behind the instrament cluster sounds like there's something crawling or moving stuff around back there? And ideas?

ManiacGT

Let's face it, it could be anything. If it bothers you then have a dealer look at it. I suspect it's normal.

lbowroom

It's likely the oil recirculating through the turbo to cool it after shutdown

Glyn M Ruck

It is mainly all the emissions gear shutting down. Ignore. Even the fuel pump can run for a few secs to bring the fuel rail up to pressure for a restart. ABS pump needs to shut down. You will hear Servo's going to default. Every Benz for a very long while has done it. Models with an excess air pump are the most noticeable.