Air Conditioning Reset?
Thread Starter
Junior Member
Joined: Oct 2019
Posts: 26
Likes: 5
GL450
Air Conditioning Reset?
I’ve recently been updating all the little things that bug me about my car. One of those things was the scratched buttons on the climate control. I bought a replacement off eBay (exact same part number), swapped it out and everything looks like it works just fine ... except it won’t blow cold air. All the buttons light up properly, the info screen shows the adjustments I make, yet it’s as if the a/c button is permanently off. The air is only as cold as it is outside, regardless of whether the a/c is on. To troubleshoot, I hooked the old unit back up and everything works just fine - it blows cold air. Do I need to perform an air conditioning reset after installing the new control unit? If so, can I do this without going to the dealer? I’ve seen articles indicating it can be done by a process that includes holding down the recirculate and defrost buttons, but it doesn’t work on my ‘16 GL450. Is there some other way I can do it from home? Or is this unlikely to fix and there’s some other issue?
I realize it’s unlikely anyone else has made this repair, but hoping I get lucky. Thanks
I realize it’s unlikely anyone else has made this repair, but hoping I get lucky. Thanks
Thread Starter
Junior Member
Joined: Oct 2019
Posts: 26
Likes: 5
GL450
My issue ended up being a programming issue that could only be fixed by the dealer. My replacement controls were off a 550, so they weren't working correctly on my 450. The dealer had to use a software program to change the setup on my replacement controls to work on my 450. The software has lots of dropdown options and the selections for my replacement were evidently different from the one I removed. They made note of how my original controls were set up and after a second try, they were able to replicate the setup and it started working. I was never able to find a way to "reset" the system on my own.
Anecdotally, when on auto, I can now see bars for how hard the air is blowing. These bars were not previously visible to me - the screen was blank. Just an example of the types of things that can be controlled with the dropdown options within the software.
Anecdotally, when on auto, I can now see bars for how hard the air is blowing. These bars were not previously visible to me - the screen was blank. Just an example of the types of things that can be controlled with the dropdown options within the software.
