HI, I have a problem with my rear defroster, I searched here and read a few post but nothing that helped me, the button light turns on, i can hear the click, check fuses but nothing, i bought a tester, checking online i saw people saying the first thing to test is the grid, now i dont see any current coming from the grid, but i do get current at the thing connecting it


If im not wrong the upper one is the antenna, and the bottom one is the defroster. It a bit rusty but it looks like its properly welded to the grid.


Theres current when i touch it and theres current all the way that thick part, it just doesnt work on the lines of the grid.

Olso, i tried pulling this part but it wasnt coming out, how do i get this part out?



Any idea would be appreciate it, thanks!

 

You are getting 12V+ at that wire when the defroster is turned ON, correct?
What about the ground connection at the other end of the grid? There should be a separate connector on the passenger side C-pillar for the ground connection. Is that good?
Also, do the side mirrors defrost when you turn the rear defrost ON?

re: trim removal, from the FSM:


These pieces use both plastic AND metal clips so exercise caution as these clips are prone to breaking.

 

Yes, i do get 12V+ when its on and the mirrors are working too.. at the other side you mean like the passenger side of the window? I haven’t check that area, I thought everything was on the driver side

 

The rear defroster is a grid that has a 12V+ connector on the left/ driver side and a ground connection on the right/ passenger side:


On the driver side you have the white wire at connector B401 which reads 12V+ when the rear defroster is turned ON:

This is the wire you verified has 12V+. For whatever reason, the B401 (+) connector is not shown on the harness layout.

On the passenger side you have the B402 connector which is your ground/ grounding strap which connects to the frame at B403:

This is connection you should check next.

Assuming you have good power and ground connections, then the issue lies with (likely) a break in the filament(s).

 

So i went and checked, the other side, the ground, looks fine too...



I checked the grid several times, havent seen any breaks in the filaments... just spotted something. but not a break..




could that be the problem? how do i check if the ground connection if fine? I also have a multi tester but i dont how to check it with that one... if thats was the problem, wouldn't it light up all the way there before the break?

In the next photo, i get a light all around the red circle.. and then the filaments until the withe line.. beyond that the tester wont light on... in no other places it turns on, the filaments, the other side, nothing... just the driver side and a bit of the filaments

 

Double post, wasnt showing the first time..

 

Set your multimeter to read DC-Voltage. With the rear defroster turned on, place the red probe on the driver-side terminal and the black probe on the passenger-side terminal. Does the meter read 12volts?

I am away from my laptop so I can't see the images clearly. What am I supposed to be seeing in the 2nd pic?

 

What i was trying to show is that i can get the tester to light up away from the thick part of the grid where the connection is, but moving it a bit to check the filaments, after around 1 cm over the filament it stops lighting up

 

I am not sure your test light is going to suffice in this case.

When you have time test for voltage using the meter as I mentioned above.

Once I get back to my MacBook I'll see what else I can find.

From what I see it is a power/ground issue.

 

I do get a reading, its not 12, just 11.87 or something, leaving the red one and testing the grid, a couple of the bottom of the grid read 0.17 and the upper part 1 was around 8 and another 0.17
Edit: the rest around 12

 

If you are receiving power and ground, and the mirrors defog, then my guess is that there has to be a break somewhere in the grid. I doubt it is the condenser as you are getting 12V.

If you have not already, download the DEF (DEFOGGER) section of the factory manual for your car from here. It will explain how to test the grid using your multimeter and some aluminum foil.

From past experience on different cars, it does not take much for these filaments to get damaged or even wear out.

 

I did test with aluminum foil, most of the filaments were giving current, except a couple of them.. sometime back checking about this, found something about a relay that could be the problem but i dont know where it is, it says is below the the driver side.. if the relay is bad, i wouldnt get any current on the grid right?

 

If the relay was bad there would be zero voltage at the grid. That, and the mirrors would not defog either. The relay is mounted behind the left-side fuse block. If it clicks when you press the button, likely it is good. Did you check both fuses?

Sounds like a break in the filament(s). Maybe others will have other ideas/ suggestions...

 

Yeah, thats what I thought, just wanted to make sure… i did check all the fuses, the ones at the lower dirver side and the fuse manual also mentions one around the battery, i did check those too.. everything that mentions defogger…

 

Ill check the filaments again a bit more careful, its just so uncomfortable to work around that area.. not a lot of space