whats the best way to do this? in my new project car there is old tint that is coming off some on the back window. should i just take a razor to it, or is their some trick? and should i worry about messing up the defrosting/demisting lines across the back window? thnx for your help

The best way I know of is to heat the tint film with a hair dryer, it will cause the glue on the sticky side to release. Don't get the hair dryer too close to the glass, don't use it on the 1500 watt setting, and clean up the residue with mineral spirits or the like.

Yes, there is a way to remove the tint without messing up the defroster wires and in my case, the radio antenna too. Spay it with water with a few drops of detergent and place plastic (garbage bag) over it for about 24 hours or until it can pull off real easy. Just keep it wet. The detergent will help the garbage bag stick. For the rest of the windows, the tint will come off with a razor. Check, but I think my tint man said a little ammonia with the water will speed things up. Good luck.
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Tom F

wow man, thnx for the info thats exactly what i needed. the tint looks like it has been partially scraped off by someone else, and i'm hoping the defroster wires aren't damaged. but if so then i guess i'd have to fix them. its something ive never done before so it would be interesting to do.

Yes you should worry about messing up the defroster grid. Scraping is definetely NOT recomended. Try calling a window tinter and ask best way to remove. The defroster grid is fragile and easily damaged.

hmmm. alright thats good to know. i know alot about volvo's. 240's specifically, but what exactly is the setup with the defroster grid. i know you flip the switch and a current is sent through the back, but what is it made of? thnx.

The defroster grid is made of an electrically conducting "paint" which is printed onto the glass sort of like a silk screen process I guess. The paint has electrical resistance so when the current passes through it, it heats up and defrosts the glass. This "paint" is fragile so you want to be careful even when cleaning the rear window. They sell a repair kit which has a copper containing paint. You paint over the break in the original (if you can find the break) and the copper in the repair paint reconnects the electrical circuit. I've found the spot where the repair is made doesn't get very warm after the repair bit the grid line works again.

thanks. so i guess only damaged lines will not work. correct? a break in one or 2 lines wont kill the entire system, just prevent current from flowing through those 2 right?

Yes, if only one line is damaged, the defroster will not warm that section of the window and you'll see the frost or fog along that line. There are about two lines broken on each of our Volvos. One of these days I'll get around to repairing them.

yeah its no biggie to have every one of them workin unless you really get frosted alot.