Need help identifying sound
 

Hi All,

I'm a new member, but not new to the forums. I've looked around but can't seem to find anything about this particular sound/problem. Any help you can provide would be great! Thanks in advance.

I have a 2013 535xi. After a night of sitting in the garage, when I go out to put the kids in the back seat, and I close the door on the passenger side (either front or rear), I hear a rattle. It sounds like a loose heat shield, sort of a metal on metal sound. It also sounds like it's coming from the front of the car, under the engine or thereabout. Right after the rattle, I hear a faint hydraulic noise. When I open and close the door again, there is no rattle.

I have a feeling that it has something to do with the central locking, but I can't easily recreate it. It does happen each morning after the car's been sitting for a while. It also appears to be related to when I open the door with the fob in my pocket, and the central locking mechanism actuates, even though the locks are already unlocked.

I've read posts here about how the 535's have various automatic mechanisms that engage at various times. I don't know if it could be one of those (e.g., climate system, turbo, water pump, ECU fan). But it doesn't seem like it would be related to those.

I would rather not take it to a dealer as a matter of principle.

Here is a video where I don't have the key fob on me when I open the door. At 0:10, you can hear a rattle or other mechanical sound when I open the door. If you turn up your volume high, you can also hear the sound of a hydraulic line pressurizing? (fuel pump?, auto leveling suspension?).


The second video is right afterward when I have the key fob on me. When I close the door at 0:07, you can hear the rattle/mechanical sound. It sounds like it's coming from the front of the car.


Please excuse the 2-year old talking about breakfast and wondering what I'm doing.

Any help identifying the sounds would be great - I don't know if it's something normal or if it's something I should take to an SA.

Thanks!
John

I honestly don't hear anything. But most likely just locking mechanism doing its job.
Why are you hesitant to take it to the dealer?

I've narrowed it down to some relays or switches clicking. I can reproduce the noise when I lock and then unlock the doors with the key fob and wait for approximately 30 seconds after unlocking. Then a relay/switch sound comes from right in the middle of the engine bay, behind the engine. I was doing it repeatedly with the hood up.

For some reason the relays actuate when the passenger doors close (either front or back) but not when the drivers side doors close. Odd.