Rear window defroster...missing lines?

[ianbarry]

This may be a silly question, but we just noticed on our rear window (2010 4 door) that the window defroster lines are not all even. One line has a small break in the line (fourth line down from the top), and then the next line down is missing about half the line. Is this normal??

[Stove]

No, it's not normal. The lines are basically long resistors that heat up when power is applied to them. Missing sections or breaks means that that line will not conduct electricity from one end to the other and it will not defrost that section of the window.

If you just bought the car, go back to the dealer immediately. They may have scraped it while prepping the car for sale. If you've had the car for a while, it's still probably worth seeing if they will fix it. Be careful of what you use to clean the rear window, the defroster lines are on the surface and can be damaged if you are cleaning with anything other than a paper towel, or a soft cloth towel. I suppose it is possible to damage them with a soft towel but you'd really have to try.

The temporary permits here in Oregon are stuck in the back window with double back tape. I've seen a bunch of people scraping the tape residue of with a razor blade after their permanent plates arrive. They scrape the defroster off with the tape residue.:eek:

[127.0.0.1]

no line should be broken. lines near where the wiper rest make a rectangle, but they
are easy to see that they are designed that way. broken (jagged edge) is ...broken

[frog13]

Good info Stove...I didn't know the defroster was a "surface" unit!.:eyebulge:

[yarrr]

Thank you sir, I had the same question, but you answered my question with your question.

4th line down is missing about 1/2 inch on the right side. Next line down has maybe 2 feet starting from the right side, and then the entire left half is missing.(right side looking at the window from outside)

[ianbarry]

So, we called the dealership where we bought the car and they said that it was like that b/c of something about the antennas in the car and that's how they come from the factory. That it was supposed to be like that and all the other Yari's in the lot were the same way.

If you look at your back window, all the defroster lines go straight from one side to the other??

[Revsson]

I thought I read that the rear window defroster was now standard equipment on the 2010.
I think on my car, it was part of an All Weather Guard package....or maybe I am thinking
of the rear wiper.

Maybe you could take pics of the entire rear window? I have a LB, so it
would be different than yours.

Doesn't the sedan have the radio antenna built-in to the rear window as well?
Have they changed the radio antenna design for the 2010? Maybe the
drawing isn't to scale? Is the radio antenna above the defroster wires?

Check out post #3 of this thread:
http://www.yarisworld.com/forums/showthread.php?t=28378&highlight=Sedan+radio+antenna
It would appear that the radio wires are "broken" if that diagram is accurate.

Defroster wires shown on page 146 of the 2007 repair manual as:
http://www.etimago.com/yaris/repairmanual/Windshield%20Window%20Glass.pdf


http://www.yarisworld.com/forums/attachment.php?attachmentid=34267&stc=1&d=1276024110

[Stove]

If its designed that way then you should be OK. Looks like you have a Sedan, I have a Lift Back and I didn't think there would be a difference in the rear defroster format. If it was me, I would go look at a few new Sedans to see if they are in fact that way.

'10 Lift back rear defroster for a reference:
10 continuous lines
the top line (11th line) wraps around the 3rd brake light

[Stove]

Maybe you could take pics of the entire rear window? I have a LB, so it
would be different than yours.

Doesn't the sedan have the radio antenna built-in to the rear window as well?
Is the radio antenna above the defroster wires?

It would appear that the radio wires are "broken" if that diagram is accurate.


Nice work, I believe you just solved the mystery. :thumbup:

The antenna is in the upper part of the window, not part of the defroster.

[ianbarry]

Absolutely correct. That diagram is pretty accurate as to our back window.

Thanks for helping me figure it out!!

[birdman]

If it's not functional you can purchase the coating and paint on the missing lines. Use quality plastic masking tape to create the stencil to make tidy lines.

[markitect]

My sedan had a broken line, it was very evident int he winter as a large section didn't defrost.

Apparently the dealer can measure the resistance of the defroster to determine if there are broken lines.