dnvnlee

Hi All,

I picked up 2023 c300 this January, and never used the rear window defroster until recently.
What I found out as soon as I pushed the defrost button when it was foggy inside was that the top third of the rear window was not defrosted while the rest of the bottom was cleared.
So, I checked the gird lines and apparently the top few horizontal lines were isolated from the end points from which the current come through(also confirmed with my voltmeter)

Does anyone have the similar issue? or is this intentional by the manufacturer? I have never seen any car with a partial rear window defroster.

Thank you in advance for sharing your thoughts!

Plutoe

wgas what others have ---run to the dealer its a warantee issue

dnvnlee

I have already contacted the dealer with a picture showing the grid lines disconnected, but he claims it is normal saying that other cars in the show room also have the disconnections.
My dealership is 2 hours away, so I just can't go visit.

Now, I just called a service center in my town and booked an appointment in two weeks.

I am really curious if this is a common issue. If not, why would they put some meaningless conductive 4-5 lines in the top?(getting no voltage so no defrosting).

giovane

Could you share a picture of the disconnected elements?

dnvnlee

Yeah, I was going to post pictures. here you go. thanks!
As you can see the top third has a lot of dots of discontinuations.

Serg675

I see the same on my rear window. I have no problem with defroster. It may that top part is not meant to be defrosted and those lines are not heaters but antennas for radio and stuff.

Cosworth2000

Yeah the antenna is located in the back windshield. I have to look at mine to make sure but I think that is normal. When you tested the voltage, what did you get?

Serg675

It was some snow today and I see that very top of rear glass doesn't defrost (it defrosts eventually when glass itself heats up but not right away). So those lines are indeed antennas but heaters.

Grant Hummel

For what it is worth, I have noticed the exact same thing in my vehicle...

Monta3

Since this seems to be by design on every 206, has anyone noticed it hindering visibility through the rear window after the defroster has reduced condensation?

dnvnlee

I get 12-13 voltages on those lines that have connections to both end sides(left & right), but the lines(mostly top few horizontal lines) that are isolated as seen in the above pics have zero voltage.

How could the discontinuations are intended by design? If a conductive line is not connected to anywhere, it cannot work as radio antennas or anything else(maybe I am just ignorant about something).

W205C43PFL

Good question.

By the way OP, by design or not I was able to confirm that is how it is on my W205 (so one generation older than your vehicle OP)

Serg675

It can be just for decoration purpose to keep look consistent. The one thing is clear that it's not some defect since all cars have it in the same way.

dnvnlee

Yeah, I thought that could be the only reason unless it is a manufacturer defect.
So I tried to find some informative postings online, and read about defroster lines interfering radio signals if they share the grid lines.
But, it still does not make sense to me. To me, regardless of the radio antenna or whatever, it seems a defect that top third is not frosted as seen in the pic (it wouldnt be defrosted even after 10 minutes).
Maybe I will simply have to admit it is the way it is.

giovane

Tell us more about the dashcam you installed in the rear. How and where did you hook it to the fuse box?

dnvnlee

The fuse box in the trunk(right hand side) has ACC(cigar Jack) & always-on fuses. So, I tapped both for a parking mode enabled dashcam.
Also you can tuck the cables in nicely around rear window, and completely hide them.

I can explain more or answer any question you may have to install a dashcam on w206.

giovane

Please open a new thread,,and please share pictures.
I'm mostly interested on how you tucked the cable and how you reached the fuse box in the trunk. Also take a picture of the fuses you tapped into.
I will be so grateful. Thank you.

ps I wrote a therad on the Audi forum years ago when I installed a garmin dashcam in my A7
https://www.audiworld.com/forums/a7-...-mini-2989144/

dnvnlee

Wow, what a well-organized detail on your work. I wish I knew you when I was installing the dashcam. I could have asked you a ton of questions lol.
Sure, I will try to post something that might be helpful for others looking to install a dashcam on w206.

The car is actually my wife's daily commuter into city(Manhattan), I will try to take photo on how I have done over the weekend although I dont have any pic taken while installing.

giovane

I took delivery now my new 2023 C Class and I confirm I have the same dotted pattern in the rear defroster grid

818benz

Same here on a 2022 w206. My 2020 w205 also has the same breaks in the defroster grid so I'm sure it's normal.