I watched three different YouTube videos prior to embarking on the cabin filter in my 2020 GLS450. Now that I've done the job, I realize that each of those videos was unclear about a couple things. So since I'm always looking for good karma, I decided to pay it forward. Here is how my job went:

Passenger foot well... My car's panel had no torx screws, which surprised me, since one of the videos mentioned them. Instead, my car had one "push expander pin" thing, which I gently loosened and pulled down/out with a small flat head screwdriver. You can see it slightly popped down in this photo, after I had started on it with the screwdriver. The pin will come all the way out.



Once the push expander pin thing was popped out, then I began pulling down on the front of the panel, which unlocked two "snap clips," one on each end of the panel (see below).



The videos are correct in stating that you need to pull down on the RIGHT SIDE of the panel, as the left side is wedged under the carpet. Next, unhook the electrical connector for the foot well lamp, so you can pull the panel down all the way. You'll notice a "hook" at the back of the panel, which matches up to a square hole (see arrow below). This is important, when you go to put the panel back.



Once the panel is fully out, you'll see the filter door, which has two turn locks. Turn them to the left, to release the filter door.



The filter door is also wedged on the left side by the carpet, but you can get it out by pulling down and to the right.



Then you can pull the filter down/out. Note the orientation, so you make sure to install the new one correctly.



The hole you see on the side of the filter corresponds to a pin on the inside of the filter door, which must line up correctly when you're reinstalling the filter door.



Now, this is where it gets comical. Please don't make fun of me, for how I did the last part. Up until this point, I haven't needed to manipulate the carpet. But after trying in vain for several minutes to reinstall the filter door (it just wouldn't align correctly), I decided that I had to pull down on the carpet, in order to have a clear shot. Of course, the carpet won't stay down on its own (it wants to snap back into position), so I have to hold the carpet down with one hand... I also need a hand to hold the filter up and in place, which keeps falling back out, due to gravity. This leaves me with NO hands to reinstall the filter door SO, you'll notice in the photo that I wedged my screwdriver between the filter and the foot well floor, to hold the filter in position... And I used a random pair of pliers to keep the carpet held down. THEN, I was finally able to get a nice clear shot at aligning the filter door, starting on the left side first and then moving the screwdriver out of the way as I finished the right side. [insert applause sound effect here] .



Once the filter door was correctly reinstalled and closed, I removed the pliers to let the carpet snap back into position, reconnected the electrical connector, aligned the rear "hook" on the panel with its square hole (see earlier photo), clicked the two "snap clips" back into position, and finally pushed the "expander pin" thing back up. VOILA!

 

Thank you for documenting and writing this up for us. Very helpful guide!

 

Good job! When you say "turn left" for the filter door locks, do you mean counter-clockwise?
How much is the new filter part?

German engineering doesn't make it easy to do the simplest stuff, huh?

 

Oh yes, when I say left, I mean counter-clockwise. I should've just said "in the direction of the arrows"

I got the new filter from FCPeuro.com. I was planning to purchase the M-B branded filter from them, but FCP also offers an OEM filter made by Corteco Micronair. Having recently replaced the cabin filter in my W222, and remembering that the M-B genuine filter was actually made by Corteco Micronair, I decided I might as well save $$ and go with the Corteco Micronair filter. (I like the Mercedes star a lot, but not enough to have it on my cabin filter...)

 

So helpful - thank you!

 

Ordering filter now, thanks.

 

You know there is two, right? The second is under the hood, right against the passenger side firewall. Easy to get to, is the particulate filter from outside air. I can’t figure out how to copy/paste the link on this app, but attached is the screen shot of the thread over on the GLE discussion that shows it. Exact same for the GLS.

if you do change that filter (which I recommend), I also recommend setting the hvac to outside air, turn it on to about midway, and then spray that intake with some Lysol to sanitize the air ducts.

I have yet to figure out how to feed the tube for the hvac coil cleaner through the duct work, but will know soon as I have ordered a camera that will let me see into the tubing. That, will absolutely clean out any odor.

 

Nicely done, thank you.

 

Well done, thx.