Johnson Window Films Dealer Resource Center

Film Removal

Rear Windows

Removal of old window film is not an easy task, when you have to do it on a rear window it is one of the most difficult to achieve. All rear windows in modern cars have very fragile defroster lines, it is imperative that these lines are not damaged when removing the old tint.

There are multiple chemicals that are marketed exclusively for the removal of window film. While they may assist with the breaking down of the adhesive they all have the same basic instructions; spray on the window film, apply a plastic covering to the window and let sit for a set amount of time in the sun.

Whether you choose to use these chemicals or choose to use the basic ammonia and water that has been the industry standard forever. The same basic techniques must be used to ensure that you do not damage the rear window or defroster lines.

Below you will find a few tricks of the trade for you to study, before you attempt to remove any film from a rear window make sure you have these tricks memorized.

Tools Needed: Spray Bottle (containing your cleaning solution), White Scrub Pad, 000 Steel Wool, Black (thin) Trash Bag, Ammonia, Water and Paper Towels

Split a large trash bag down the side and spread over the rear window.
Step 4 – cover exterior of window with trash bag
Trim bag into a 1 piece pattern.
Step 5 – trim to make a 1-piece pattern
Hang pattern on glass using mounting solution.
Step 9 – place trash bag onto interior of window
Park car in sun and let bake to soften adhesive.
Step 10 – park in the sun
Park car in sun and let bake to soften adhesive.
Step 12 - peel film back
Using the spray bottle with the cleaning solution wet the exterior of the rear window, clean as you would for a normal installation prior to cutting your pattern.
Split the trash bag* down one side and across the bottom. Unfold so that you have a single large piece. *It is important that you not use a thick trash bag, the thinner the better so the bags can me formed to fit the window more easily.
Wet the exterior of the rear window again.
Cover the exterior of the window with the large opened piece of trash bag.
Smooth the bag on the rear window to remove creases. Trim the bag to 1" larger than the black border to cover the complete window.
Take the trimmed bag into the rear of the vehicle, and place on the rear deck. Much as you would when preparing to install window film.
Spray the interior of the window with your cleaning solution.
Wet the window again with an ammonia and water mixture of 2/3 water to 1/3 ammonia (use a mask for ammonia fumes if needed).
Place the trash bag over the interior of the rear window. Tucking it in as much as possible around the rear deck etc. Almost as if you were installing the bag on the rear window.
Park the vehicle in the sun with the rear window facing the direction in which it will receive the most sun based on your location.
Leave the vehicle in the sun for at least 30 minutes while trying not to allow the ammonia to evaporate.
After 30 minutes, starting in a top corner, peel the film and the bag away from the glass. If the film peels in layers (delaminates) stop and repeat the process from step 8 to 11 and check again in 30 minutes.
Once film is removed re-mist interior of rear window and scrub off any left over adhesive using a white scrub pad or 000 steel wool. Be careful when scrubbing on defroster lines.
Wipe off moisture and clean the window with your cleaning solution, to remove all traces of the ammonia mixture.
Helpful Tips:
Have the customer bring in the vehicle on a hotter day, if possible.

Remember to remove the brake light before you cover rear panel or use ammonia mixture.

Point to Remember:
It is imperative to get the ammonia mixture off the window, ammonia and window film adhesive do not play well together. If ammonia is on the window when you perform your installation you can almost guarantee you will be seeing this automobile again in a few years or so.

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