09 Rear Defrost issue and how to remove the tab covers

[ABNTGR]

2009 XLT. Yes I have looked in the archives but nothing seems to be similar.

I tested the grid and I have 11.9 volts all across the grid, on the positive side on the bus bar and on the connector, as well as on the ground side on the bus bar. I can't figure out how to take the cover off the negative side where it connects, so I can't test that.

Any thoughts on what could be wrong? The light on the button comes on, I hear the click of the relay when I turn it off and on....

From what I understand the voltage should drop as I move across from the positive to the ground side, right?
Visually there are no breaks in the grid that I can see.

Anyone know how to remove the plastic cover that the wiring is in so I can see if the connections/tabs are good? I'm leaning towards a bad ground but I can't get the plastic cover off where it connects to the window.

Thanks in advance!

 

[Rcflyer330]

If you measure at the bars on each side of the glass it should read battery voltage with the car off or ~14v car running. If you are getting ~ zero then one of the tabs is broken.

To get the cover off I used a small screw driver and there is clips on the side that have to pop off then the cover ends will slide off. ( note when I did this a couple of the little tabs broke so there is probably a better way). 11.9 volts across the grid would burn it up are you shure that is not millivolts.

Also what is the exact problem? I am guessing it will not clear the window when it is on. A quick check I have to see if it is working is when it is cold out turn on the defogger then fog up the out side of the window by breathing on it and within a few seconds you should see the grid lines and the window defogging.

I can tell you from expearance that the repair products for tabs and grid work the only problem is when you go to clean the inside of the window you will have to repaint the grid line. And with the tab I repaired It worked but broke again. At this point I am ready to buy a new window because every year I have to repair my repairs again. Very annoying this is the third year I have done this. But the cost of a new carlite window is ~$500 and for an aftermarket one from ebay is ~$250.

I hope you get your repaired without the problems I had.

 

[ABNTGR]

Yes, it's volts. Everything I have read online says that is correct. And it should drop voltage as it moves across the glass...it should be approximately 6 volts in the middle.

The problem is that it's not heating up and melting the ice or the fog.

Thanks for the info on the ebay glass!

 

[Rcflyer330]

that's an odd one. are you getting the voltage drop to ~6v in the middle?

try prying of both of the covers. the long one has 4 clips on each side once they are unclipped the cover will flex enough to slide the ends off.

if the tabs are still connected take an ohm reading between the connector and bus bar should be around 0. if it is higher than the tab is not connected.

also a cheaper way to fix it is to just install a new grid from
http://www.frostfighter.com/index.htm
they make one that will install directly to your stock wiring for around $75

 

[ABNTGR]

Found the problem. Once I got the cover off the tab on the drivers side (ground) was off. I used the kit from the local store to reattach it but it didn't work, either I didn't mix the packet of brown adhesive well enough or something else, there was no conductivity. I rigged it back on with 'aluminum tape' and got it to work. Sure enough as you go across the grid from passenger to drive side the voltage drops and it worked just fine. I am going to try the silver adhesive from frostfighter.com and see how that works. At least I know the problem and the fix now! Also, while I had the covers off on both sides I drilled some small holes in the cover just above the tabs so next time I can just stick my meter probe in and test the contact directly.

Thanks for the help.

 

[02XLS4WD]

Found the problem. Once I got the cover off the tab on the drivers side (ground) was off. I used the kit from the local store to reattach it but it didn't work, either I didn't mix the packet of brown adhesive well enough or something else, there was no conductivity. I rigged it back on with 'aluminum tape' and got it to work. Sure enough as you go across the grid from passenger to drive side the voltage drops and it worked just fine. I am going to try the silver adhesive from frostfighter.com and see how that works. At least I know the problem and the fix now! Also, while I had the covers off on both sides I drilled some small holes in the cover just above the tabs so next time I can just stick my meter probe in and test the contact directly.

Thanks for the help.

I know this thread is just about 4 years old but was wondering if that frostfighter product worked for anyone? I have a similar problem with the disconnected tab.

 

[ABNTGR]

Hi. I ended up using the frost fighter product and it has worked great! Four years and it's still working. I took great care to follow the directions. If I recall correctly I lightly sanded the 'bar' on the driver side to expose fresh metal from the original grid and the I poured on the goop and made sure it stuck. The instructions say something about having it cure, so I put a little space heater in the back of the truck to heat things up for several hours. It may have been overkill l but I haven't given it a second thought since then. Hope this helps!

 

[02XLS4WD]

Good info. thanks for the reply. I was considering just soldering the connection but discovered the "tab" on the end of the wire appears to be a connector with a plastic housing that does not separate from the metal so might go the glue route. Option 2 was to cut the old connector off and wire a new tab (male and female end) on.