2020 GLC63 CEL + Multiple warnings after heavy rain

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Jul 13, 2020 | 04:16 PM
  #1  
Hi all,

Picked this car up new back in November, no real issues aside from a little rattle here and there and MBUX shutting down mid drive once or twice.. was annoyed when it happened but its been some time and no issues.

Last month after washing the car at home, I get in to drive and the speakers seemed dead. no radio, no bluetooth, no CarPlay working, no beeps or chimes when turning the car on and off, thought it was weird and maybe blown fuse, no errors lights anywhere. I let the car sit overnight and by the morning everything was back to normal, weird.

No issues since then, until this past Friday. We had a good amount of rain here on Long Island, after the storm I got in the car and turned it on, everything seemed fine until I put the car in reverse. Seemed like every possible warning light lit up on the dash, CEL, 4matic inoperative, brake assist inoperative, traction control inoperative, lane assist, and on and on. MBUX said detected a breakdown and ask if I want to call roadside. I turned the car off and left it there for an hour. Came back and only check engine light was on, no other warnings. Took the car for a quick spin and it felt a bit jumpy and stuttered more than usual. I let the car sit over the weekend and come Sunday the CEL was gone..

I have from time to time noticed condensation on the inside during a rain storm. my assumption is there is some sort of leak happening that is causing the electronics to go bananas. I dropped the car off at the dealership today and before I left, the service manager started talking to me about diagnostic fees because of water, and if I left a window open none of this is covered, yada yada. Gave me a bad feeling about all of this..

I know for a fact there was nothing left open..

Anyone deal with similar issues? any advice on how to handle?

Thank you
L
Reply 0
Jul 13, 2020 | 04:57 PM
  #2  
You can't get an AMG wet...that is what garages are for....
Reply 0
Jul 13, 2020 | 05:26 PM
  #3  
Nope, this is what garages are for....lol



Reply 1
Jul 13, 2020 | 06:05 PM
  #4  
Funny cause I usually keep it garaged, left it out to let the rain wash the pollen off. This is what I get
Reply 0
Jul 13, 2020 | 07:51 PM
  #5  
Quote: Hi all,

Picked this car up new back in November, no real issues aside from a little rattle here and there and MBUX shutting down mid drive once or twice.. was annoyed when it happened but its been some time and no issues.

Last month after washing the car at home, I get in to drive and the speakers seemed dead. no radio, no bluetooth, no CarPlay working, no beeps or chimes when turning the car on and off, thought it was weird and maybe blown fuse, no errors lights anywhere. I let the car sit overnight and by the morning everything was back to normal, weird.

No issues since then, until this past Friday. We had a good amount of rain here on Long Island, after the storm I got in the car and turned it on, everything seemed fine until I put the car in reverse. Seemed like every possible warning light lit up on the dash, CEL, 4matic inoperative, brake assist inoperative, traction control inoperative, lane assist, and on and on. MBUX said detected a breakdown and ask if I want to call roadside. I turned the car off and left it there for an hour. Came back and only check engine light was on, no other warnings. Took the car for a quick spin and it felt a bit jumpy and stuttered more than usual. I let the car sit over the weekend and come Sunday the CEL was gone..

I have from time to time noticed condensation on the inside during a rain storm. my assumption is there is some sort of leak happening that is causing the electronics to go bananas. I dropped the car off at the dealership today and before I left, the service manager started talking to me about diagnostic fees because of water, and if I left a window open none of this is covered, yada yada. Gave me a bad feeling about all of this..

I know for a fact there was nothing left open..

Anyone deal with similar issues? any advice on how to handle?

Thank you
L
Drove mine in heavy rain, car washes, etc. Never had these problems. Take it to the dealer.
Reply 0
Jul 13, 2020 | 10:29 PM
  #6  
Assuming the window/sunroof were not inadvertently left open, it is ludicrous to think the car can't tolerate rain. I'd be livid.
Reply 0
Jul 14, 2020 | 01:03 AM
  #7  
Quote: Assuming the window/sunroof were not inadvertently left open, it is ludicrous to think the car can't tolerate rain. I'd be livid.
exactly my thoughts. It’s absurd, and the SA’s first instinct was to bring up possible diagnostic charges if they can’t find a defective seal, implying I must’ve left something open
Reply 0
Jul 14, 2020 | 10:13 AM
  #8  
Quote: Nope, this is what garages are for....lol


Weedeaters, pink bikes and vacuums?
Reply 0

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Jul 14, 2020 | 12:03 PM
  #9  
My 2020 dash went out in the first 2 months of having it. I’d take the car in and let them run a diagnostic. Most likely needs to be updated with possible new software

King
Reply 0
Jul 14, 2020 | 01:40 PM
  #10  
Quote: My 2020 dash went out in the first 2 months of having it. I’d take the car in and let them run a diagnostic. Most likely needs to be updated with possible new software

King
thank you for the response! I dropped it off yesterday, we’ll see what they come back with.
Reply 0
Jul 14, 2020 | 02:40 PM
  #11  
Interested to hear what they find, hopefully it's not a "no trouble found"...
Reply 0
Jul 15, 2020 | 01:40 PM
  #12  
So far the only update I’ve received is multiple error codes involving “communication with main engine control unit” .. they are saying the rain was just a coincidence..

according to the SA the tech is digging through all the wiring to make sure everything is okay. Will take a couple of days.

we will see..
Reply 0
Jul 30, 2020 | 03:46 PM
  #13  
Any update on this?
Reply 0
Jul 31, 2020 | 04:26 AM
  #14  
Quote: Any update on this?
yea sorry, meant to update the thread when I got the car back.

SA said the tech found defective pins in the wires connecting the “main engine control unit” and that the errors after the rain were a coincidence (I’m not really buying that) .. they replaced everything and no issues since.

All in all took about a week and a half.
Reply 0
Jul 31, 2020 | 08:55 AM
  #15  
Good deal, I'm glad it got sorted out, I'm sure it was a bit frustrating at the time. Thanks for the update!
Reply 0
Jul 31, 2020 | 09:15 AM
  #16  
That's the problem when MB takes an entry level product, throws a 63 on it. 90K for a GLC? No way! Same build quality as the 40K product, same issues.
Reply 1
Jul 31, 2020 | 04:50 PM
  #17  
Quote: That's the problem when MB takes an entry level product, throws a 63 on it. 90K for a GLC? No way! Same build quality as the 40K product, same issues.
...but they are fun plus the E63 has had a ton of issues so I am not sure on your theory????????????
Reply 0
Jul 31, 2020 | 05:17 PM
  #18  
Quote: ...but they are fun plus the E63 has had a ton of issues so I am not sure on your theory????????????
They ARE fun for sure. As for the E63, similar situation but a better build for sure. Not sure I'd spend 125K on an E class either. Regardless, I respect everyone's choices. Cheers.
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