How To Fix A Rear Window Defroster (11 Steps)
- Clean The Window. Wipe the window with a mildly damp cloth. Don’t use anything abrasive and do make sure that the...
- Sand The Tab Down. If the tab has broken off, use sandpaper to sand down the rough solder. Even if you have a...
- Clean The Tab. Use alcohol solution, usually provided with the repair kit, to clean the...
How do you fix a broken window defroster?
There are a couple of ways you can repair your defroster yourself. The first is to make sure that the main tabs on the side of the window — the ones that carry the electricity to the grid — are strongly attached to the defroster itself. You can do this with a tab adhesive product.
What to do if your defrost line is not working?
The days of having to live with a non-functioning grid of defrost lines are over. The latest defroster repair kits are amazing, addressing almost every possible problem that can arise in your system. The first step is always troubleshooting. You need to figure out why your defroster isn't working.
What to do if your rear window defroster grid is packed in?
A worse scerio: The rear-window defroster grid has packed it in completely, requiring you to either drive blind (bad idea), or resort to scraping the rear window clear with your trusty wooden-handled snow scraper (really bad idea). Now what?
Do you need a rear window defroster?
But the defroster became standard issue for rear windows, and the world was a better place. That is until something put a little nick or scratch in one of those delicate lines across the glass.

How do you fix a rear window grid?
5:478:04How to repair rear window defroster tabs and grid lines. Defogger repair ...YouTubeStart of suggested clipEnd of suggested clipMake sure there is a good seal between the stencil. And the glass remove all of the air bubbles fromMoreMake sure there is a good seal between the stencil. And the glass remove all of the air bubbles from under the stencil shake the bottle of repair compound.
Can you solder rear window defroster?
Even though the electrical tabs are soldered onto the defogger grid at the factory, avoid the temptation to solder the replacements. If the heat cracks the glass, you will have to buy a new window.
Can you repair a heated rear window?
Rear window heaters fitted by manufacturers are printed on to the surface of the glass or stuck on with special adhesive. Small breaks in an element can be repaired with special conducting paint. One of the most common and simple problems is a blown fuse. Find the fuse protecting the heated rear window circuit .
What are defroster lines made of?
Rear Window Defrosters Automotive rear window defroster are sophisticated surface heaters. The grid pattern of thin brown horizontal lines are made from a silver ceramic conductor which is silk screened, essentially painted, onto the inside of the rear window and then baked at high temperatures.
How much does it cost to repair rear window defroster?
Bad news: A new rear window can be more than $400, including installation. Good news: You can fix it yourself for less than 10 bucks. Really. Start by going to the auto parts store and picking up a rear-window defroster-grid repair kit and/or a defroster tab repair kit, depending on the damage you need to fix.
How much does it cost to fix a rear defroster?
between $45 and $80In terms of both parts and labor, fixing a front or rear defroster will cost roughly between $45 and $80. Properly functioning defrosters are essential to safe driving, especially if you live in an area with a harsh winter climate.
How do you defrost a window when defroster doesn't work?
Here's what you do: Mix ⅓ part water and ⅔ part isopropyl or rubbing alcohol together and pour into a spray bottle. Spray the solution onto your windshield, and voila! You'll see the ice disappear instantly.
What are the lines in the back window of a car?
Because the glass of a windshield can be obscured by condensation, the lines on it acts as defrosters. The lines are actually small wires that are built into the glass to quickly defrost a rear windshield. The lines are able to remove condensation in minutes. The lines are also known as secondary defrosters.
What do you do when your defroster doesn't work?
Here's how to fix a front windshield defroster:With the engine off and cold, check the coolant level. If the coolant is low, fill it up. ... Check the heating, ventilation, and air conditioning (HVAC) controls. ... Check if you can hear the blower motor running. ... Check for power at the blower motor.
Can I tint over my defroster lines?
The short answer is, yes you can! The long answer is as follows. Defroster wires get very hot to help you quickly regain visibility in the winter months. This heat does not damage modern window films because of huge gains in the technology surrounding window film manufacturing.
How hot does a rear window defroster get?
The average defroster grid heats to approximately 85°+ F (29° C) and are very effective in clearing rear windows in difficult winter conditions.
How do you test a rear heated windscreen?
0:273:13Testing a Window Defroster Grid - YouTubeYouTubeStart of suggested clipEnd of suggested clipAnd as its dropping voltage you'll see it gets dimmer. As it goes. Across. You know you'll have 12MoreAnd as its dropping voltage you'll see it gets dimmer. As it goes. Across. You know you'll have 12 volts 6 volts 3 volts eventually down to 0 volts over here where it won't bite at all.
How does a heated rear window work?
The grid on the rear window is known as a rear window defogger. It is a thin electrical element that power runs through. The resistance in the element causes it to heat up, which warms the glass. The heat melts a small amount of ice and snow, and clears the fogginess from the rear window.
How does a rear window defroster work?
The rear defroster is powered by electricity and operated by a dashboard switch. Turning it on activates a grid of wires, visible as thin lines on the inside of the glass, that heat the rear window to defog the glass and melt frost, snow and ice.
Why does my demister not work?
If your car has low coolant due to a leak, the heater and front demister won't work properly. Your vehicle may also be at risk of overheating. Bad blower motor – The blower motor forces air through your heater core, allowing it to warm up. If the blower motor fails, the demister will cease to work.
How to fix a broken rear defroster?
How to Repair a Broken Wiring Stud in your Rear Defroster. Mix a batch of conductive epoxy to reattach the spade plug. You may think that a broken wiring stud (or spade) connector on your rear defrost grid means that you will never have a rear defogger again.
What are the problems with rear defrosters?
The two most common problems with rear defrosters are: A break in the conductive lines. The deterioration of the spades that connect the grid to your car's wiring.
Can you pass a cloth to the back seat?
Sure, there was the warm air blowing from the defrost vents at the base of the windshield, but this had little, if any, effect on the back window at the far end of the cabin. If you had kids, you could pass a cloth to the back seat and give orders to keep the rear window clear. Car seats were optional in those days.
How to fix a broken defroster?
The first is to make sure that the main tabs on the side of the window — the ones that carry the electricity to the grid — are strongly attached to the defroster itself. You can do this with a tab adhesive product. Next, you can correct any breaks in the defroster grid by painting ...
How does a rear defroster work?
Instead of hot air, the rear car defroster sends electrical current through a small grid made of a mixture of metal and resin that is attached to the glass with an adhesive. When activated, the resistance in the metal generates enough heat to evaporate fog. In most cases, it can also melt snow and ice to prevent it from sticking to the window.
Why does my rear defroster work differently?
Also known as a defogger, your rear defroster has to work very differently from the one up front, due largely to the absence of any hot air ducts linking it to the vehicle’s climate control system. Fortunately, the solution to this quandary is very simple, and it involves harnessing the 12-volt electrical system in an automobile to generate heat.
What does scraping a rear window do?
The act of scraping or cleaning a rear window can sometimes sweep away enough of the metal to interrupt the circuit, which , in turn, prevents electricity from being transmitted to that segment of the car defroster.
Does a rear defroster stop working?
You probably don’t think much about your rear car defroster until it stops working properly . Usually, the decline is gradual, with only part of the back glass getting cleared of fog, snow and ice. Then, the problem eventually spreads to the point where your visibility in the rearview mirror is significantly compromised.

Causes of Damage
- The defroster consists of electrical tabs, which are soldered onto the grid, and a length of wire. Any damage to the tabs or the wire can stop the defroster from working. Attempting to clear ice from the inside of the window can cause damage, and so too can any protruding items that might catch on the wires. The tabs can also come loose if they are knocked when you pack the trunk t…
Assess The Damage
- There are various repair kits available, including those that repair just the tabs and those that repair the wires. Both are relatively inexpensive and do the job, but before you start, you need to know the extent of the damage you’re dealing with. If part of your window still clears, there is a good chance that the wire has become damaged near where the ice ends and the clear window …
Materials and Tools Needed
- Be aware that some repair kits will include accessories like sandpaper, so open your repair kit to see what is included and what else you need. Some kits include everything, and they should include the glue or applicator that you will need. Otherwise, the only equipment you might need that isn’t included is sandpaper. In most cases, you will need t...
How to Fix A Rear Window Defroster
- Assuming it’s the right temperature and you have all the required equipment in your repair kit, the steps to repair the rear window defogger are as follows:
Conclusion
- A broken rear defogger can present you with a challenge. You will either need to carefully remove ice yourself, every time you want to drive in cold conditions, or may have to replace the rear window or entire rear panel. Alternatively, repair kits are available that provide you with everything you need in order to make the repairs. They are inexpensive but their instructions can be difficul…