Jump to content
  • Sign up for FREE! Become a GM-Trucks.com Member Today!

    In 20 seconds you can become part of the worlds largest and oldest community discussing General Motors, Chevrolet and GMC branded pickups, crossovers, and SUVs. From buying research to owner support, join 1.5 MILLION GM Truck Enthusiasts every month who use GM-Trucks.com as a daily part of their ownership experience. 

Rear window defroster buzzing


Recommended Posts

2020 Sierra SLT

 

This morning I noticed a buzzing noise coming from the rear of the cab. The sound came from the right bottom of the rear window. The buzzing stops when I turned the rear defroster off. Turned the rear defroster back on, the buzzing started again.

 

Has anyone else had, or noticed, this problem? I tried to find a connecter to see if it was loose but couldn't find it.  I don't think it's affected the performance of the defroster, at least not yet. I figure it'll require a trip to my dealership's service department, which I'm not a huge fan of. 

 

Thanks for your time,

DC

 

 

Link to comment
Share on other sites

24 minutes ago, redwngr said:

I'd be getting it looked at, and I'd avoid using it until after. 

 

 

absolutely.

 

I have disabled the defroster from automatically coming on with remote start and also made an appointment with the local dealership.

Link to comment
Share on other sites

Would love to know what you find out.  My 2020 RST just just started doing this same thing three days ago.  Same spot too - passenger side right above the rear seat.  Currently have 7000 miles on the truck.  I have only noticed it in the morning when the temp has been about 35 degrees.  Doesn't seem to be doing it later in the day.  No idea if temp has anything to do with it.   

 

If you get yours fixed soon, can you let me know what was found?  I'll get mine in at some point, but it's always a hassle to take it to the dealer!

 

Thanks! 

 

 

Link to comment
Share on other sites

On 1/25/2021 at 11:24 AM, Daryl Casey said:

absolutely.

 

I have disabled the defroster from automatically coming on with remote start and also made an appointment with the local dealership.

The buzzing is electricity arcing. Luckily it will be under warranty for you. There is a recall but it only covers vehicles in certain cold weather areas. Canada made GM recall all trucks with the sliding rear windows with defrost. 

  • Like 1
Link to comment
Share on other sites

On 1/29/2021 at 11:33 PM, S Schultz said:

Would love to know what you find out.  My 2020 RST just just started doing this same thing three days ago.  Same spot too - passenger side right above the rear seat.  Currently have 7000 miles on the truck.  I have only noticed it in the morning when the temp has been about 35 degrees.  Doesn't seem to be doing it later in the day.  No idea if temp has anything to do with it.   

 

If you get yours fixed soon, can you let me know what was found?  I'll get mine in at some point, but it's always a hassle to take it to the dealer!

 

Thanks! 

 

 

If it's arcing and starts a fire, that will be alot more hassle than taking it in to get repaired....

Link to comment
Share on other sites

13 hours ago, redwngr said:

If it's arcing and starts a fire, that will be alot more hassle than taking it in to get repaired....

The arcing can produce a localized heat source and make the window explode. I have video of mine smoking before I pulled the fuse and submitted it to the .gov. They won't reply unless it becomes a recall. 

  • Like 1
Link to comment
Share on other sites

On 1/29/2021 at 11:33 PM, S Schultz said:

Would love to know what you find out.  My 2020 RST just just started doing this same thing three days ago.  Same spot too - passenger side right above the rear seat.  Currently have 7000 miles on the truck.  I have only noticed it in the morning when the temp has been about 35 degrees.  Doesn't seem to be doing it later in the day.  No idea if temp has anything to do with it.   

 

If you get yours fixed soon, can you let me know what was found?  I'll get mine in at some point, but it's always a hassle to take it to the dealer!

 

Thanks! 

 

 

Will do

Link to comment
Share on other sites

7 hours ago, Daryl Casey said:

My dealerships service dept is very backlogged due to a COVID outbreak. Not sure when I'll be able to get my truck in for this issue, but please share what you find out with us here!

Well, my dealer can't find anything wrong.  My defroster was buzzing/arcing real bad on Saturday.  That afternoon, I happened to open the rear sliding window.  The problem has not happened again since doing that.  Have you dried cycling your window by chance?  Not even sure that's what caused it, but I had a feeling that's what the dealer would say when I dropped it off.  They couldn't duplicate the problem, and could not locate any service bulletins related to it.  Hopefully it doesn't happen again, but it's documented if it does.  Good luck with yours.

Link to comment
Share on other sites

  • 4 weeks later...

I had this happen to my 20 RST.  I noticed there was a small leak and there was water coming off the track for the sliding window and running down the glass across the wires.  The wires were really hot.  I assumed it was the water sizzling on the wires because it only did it some of the time.  Dealer took it in and replaced the window.  Just got it back today so i'm hoping that solved it.

 

Link to comment
Share on other sites

  • 4 weeks later...
On 1/31/2021 at 12:39 PM, Abiker21 said:

The buzzing is electricity arcing. Luckily it will be under warranty for you. There is a recall but it only covers vehicles in certain cold weather areas. Canada made GM recall all trucks with the sliding rear windows with defrost. 

I believe you are 100% correct. There seems to be a conductivity issue. I bet if you look closely at the area the buzzing is coming from a small arc can be seen at night and maybe even a small burnt spot!!!

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

  • Similar Content

    • By midwestdenaliguy
      I've always thought the rear headrests were awful short and stubby in my 2016 Sierra Denali Crew Cab. For adult passengers and my kids once they are tall enough, I wanted a better option. After digging around in here I noticed that in pics of double/extended cabs the rear headrests were different and looked taller than my crew cab headrests. There are a few options on ebay and I found rear headrests from a double cab that match my black leather interior. Thought I'd show comparison pics of the crew cab headrests vs the double/extended cab headrests. You get about an inch more of coverage, so nothing spectacular but it is more. Headrests in good shape ranged from $50-$200 in my ebay search, so it all depends on how much you want to pay for the additional head coverage. Next on the to do list will be to add notches down the steel leg mounts to have them stay higher than the factory notches. I did notice the double/extended cab headrests stay locked in position much better than the crew cab ones. Why? I have no idea, but the crew cab ones would fall down even when going over a slight bump in the road.
       
      In the last pic I just slid the crew cab headrest legs behind the middle seat to have something there. It stays in position pretty good, won't be able to extend up but it doesn't move at all while driving.
       
       





    • By Greg B
      Yesterday was my first time driving my truck in snow and my wiper blades froze to the windshield.  It wasn't snowing real hard, and it's garage kept, so I started with a clean windshield.  The whole defroster and wiper design is terrible.  The defroster vent sits high on the dashboard, so it misses the lower few inches.  But then the wipers sit so low on the windshield that it is actually below where the windshield and dashboard meet.  So even if the defroster did blow lower, the dashboard still blocks the air from getting down there.  There is no way I see to heat that part of the windshield or the wipers.  You can see it in the pic.  Luckily I was close to home, but I would think on a longer trip the only way to take care of it would be to pull over and spray de-icer on it or clear it by hand.  But even when it did come free, the wipers worked for crap because they were frozen solid.  
      The only other thing I can think of is installing some kind of defogger strips like the rear windows have, but I don't see anything like that online.  I felt it was such a safety issue I filed a complaint with NHTSA.  Anyone else have any experience with this and any fixes.  My first oil change is coming up so I will be seeing what the dealer says, but I don't see anything they'd be able to do, it the design of the truck that sucks.  

    • By 2020SilveradoCC
      Anyone else get a buzzing sound in the B pillar when accelerating around 30+ mph? Sounds like a plastic type buzz. Taking the truck in for the recall on Tuesday, if anyone has any suggestions to help point them in the right direction I’d appreciate it!
    • By MacAaroni
      Im wondering what issue would cause the rear wheel cylinder ears that hold the brake pads, to shear off? I have a 2006 GMC Sierra 1500 2WD 4.8L with rear drumbrakes.
       
      I replaced the rear wheel cylinders and brake shoes on both sides. After 5-10 minuets of driving, i had extremely loud squealing from the rear when braking to a stop. I took off the drums to check and saw that the passenger side wheel cylinder ears had sheared right off, but only on the outside of the truck, not inside ears. The shoe that is towards the front of the truck also was pushed out towards the inside of the drum and was rubbing on the inside facing where the hub sits so that must be what was causing the squealing. But i dont understand what would cause such a force to shear the wheel cylinder ears right off. Drum out of round? Before i replaced the shoes, both passenger and driver side shoes towards the front were almost to the metal shoe backing plate, so thats why i replaced them.
       
       
    • By AdriansAvalanche09
      I have a 2009 Avalanche, both rear windows wont operate with the front or individual switches. I replaced the main driver side switch with no success, I checked all the wires and fuse box on driver side. 
       
      Any ideas? 
  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Forum Statistics

    240k
    Total Topics
    1.4m
    Total Posts
  • Member Statistics

    294,935
    Total Members
    8,960
    Most Online
    David Rini
    Newest Member
    David Rini
    Joined


×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.