Unable to Reset Sunroof After Battery Replacement
Thread Starter
Member
Joined: Jan 2010
Posts: 181
Likes: 6
From: New York, NY & Baldwin, Long Island, NY
14' C300, '07 G500 & '02 C240
Unable to Reset Sunroof After Battery Replacement
Hi Everyone! Today I recently replaced an aging battery on my 2014 C300. The sunroof can open and tilt up automatically, but when I close it, it does a jerking start/stop behavior, while it closes which is weird. Its never done that till I changed the battery.
I tried resetting or resynching it, by putting the key in position 2 (engine is off), I pressing the button up to tilt smoothly, after its fully tilted, I continue to hold the pressed button the in the raised position for 5 seconds. I then pull the button down the moonroof still hesitates while it closes, but it eventually closes all the way. I hold the button in the down position for more than 5 seconds, it does not reset.
Does this mean I have to take it to the dealer? I really dont want to pay them for this! 😞
I tried resetting or resynching it, by putting the key in position 2 (engine is off), I pressing the button up to tilt smoothly, after its fully tilted, I continue to hold the pressed button the in the raised position for 5 seconds. I then pull the button down the moonroof still hesitates while it closes, but it eventually closes all the way. I hold the button in the down position for more than 5 seconds, it does not reset.
Does this mean I have to take it to the dealer? I really dont want to pay them for this! 😞
Senior Member
Joined: Feb 2015
Posts: 435
Likes: 81
From: New Zealand
W204 C200, BMW E30 M3, 1980Gt Mini, Toyota Corona, KTM 200 EXC.
Hi,
Take it to the dealers for a reset I have had to do mine twice and both times it happened a few weeks prior to the battery failing. I found no way of doing it at home even following the reset guidelines.
Take it to the dealers for a reset I have had to do mine twice and both times it happened a few weeks prior to the battery failing. I found no way of doing it at home even following the reset guidelines.
Thread Starter
Member
Joined: Jan 2010
Posts: 181
Likes: 6
From: New York, NY & Baldwin, Long Island, NY
14' C300, '07 G500 & '02 C240
Senior Member
Joined: Feb 2015
Posts: 435
Likes: 81
From: New Zealand
W204 C200, BMW E30 M3, 1980Gt Mini, Toyota Corona, KTM 200 EXC.
Thread Starter
Member
Joined: Jan 2010
Posts: 181
Likes: 6
From: New York, NY & Baldwin, Long Island, NY
14' C300, '07 G500 & '02 C240
Here is are some videos demonstrating the pronlem and my failed attempts at resetting it lol.
Last edited by Vlad-II; Mar 9, 2021 at 11:55 PM.
Thread Starter
Member
Joined: Jan 2010
Posts: 181
Likes: 6
From: New York, NY & Baldwin, Long Island, NY
14' C300, '07 G500 & '02 C240
Just wanted to update everyone on this issue. So I had to do an oil change and annual service for my car, so I took it to a local Mercedes Benz mechanic (who does work on the side) and he was able to reset it, with his MB Star Diagnostic tool. Apparently there was an issue with the sunroof computer module or some bad data on the ECU after the battery change or something like that and he was able to clear it and it now closes smoothly without the stutter.
Unfortunately when this happens and you are unable to reset it yourself you have to take it to the dealer or a certified mechanic can reset it for you (as stated in the manual). The mechanic was super friendly and he did not charge me anything to fix it. Was a really quick fix actually. Apparently this occurs whenever the Sunroof is left open while changing the battery. Which is why its super important to close all windows and sunroof when the battery is changed so that the system doesn't go out of whack. Or if you are changing the battery use a backup battery first.
The Sunroof closes perfectly there is some sort of click that happens as you saw in the videos, but he told me to leave it alone for now. It could be something on the track or something of that sort, but anyway I'm not too worried because I mainly use the tilt function because it gives the car a nice aesthetic. I rarely open the Sunroof on the open position unless i'm in the city and want to see the skyscrapers haha.
Unfortunately when this happens and you are unable to reset it yourself you have to take it to the dealer or a certified mechanic can reset it for you (as stated in the manual). The mechanic was super friendly and he did not charge me anything to fix it. Was a really quick fix actually. Apparently this occurs whenever the Sunroof is left open while changing the battery. Which is why its super important to close all windows and sunroof when the battery is changed so that the system doesn't go out of whack. Or if you are changing the battery use a backup battery first.
The Sunroof closes perfectly there is some sort of click that happens as you saw in the videos, but he told me to leave it alone for now. It could be something on the track or something of that sort, but anyway I'm not too worried because I mainly use the tilt function because it gives the car a nice aesthetic. I rarely open the Sunroof on the open position unless i'm in the city and want to see the skyscrapers haha.
Super Member
Joined: Mar 2011
Posts: 803
Likes: 37
From: Bay Area, CA
2011 C300 Sport, P1, MM, Wood, Heated FS, DIY rearview camera.
Thanks for the update especially for the point of closing sunroof when changing battery. When i changed battery five years ago I was sure sunroof was closed. I almost never leave it open parked in the garage. Therefore, after battery was replaced, nothing went wrong.
