The Quickest Way To Defrost Your Car With The Defroster (2022)

It’s pretty frustrating when you’re in a hurry but find out after getting into your car that you won’t be able to drive away anytime soon because of fogged up or frosted windshield and windows. This is where the defroster in your car comes into play. A vehicle defroster is handy for getting rid of frost or ice on your windshield on those cold winter days.

Fortunately, if you know how to use the car defroster properly, you can quickly clear up the glass and hit the roads. In this car maintenance tips guide, learn how a car defroster works, including both the front and rear defroster, and a step-by-step guide on how to defrost your windshield and windows on cold days as well as defogging them on rainy days.

How a Car Defroster Works

Hot air holds more moisture in it than cold air, or in other words, at high temperatures, moisture is easily suspended in the warm air. But when the weather is cooler, moisture in the air is no longer suspended but is released and condensed into all those little water droplets that fog up your car’s windshield and windows.

You will see this happens on cold mornings, when the overnight ambient air drops in temperature while the air inside your vehicle is still warmer, even when you parked your car outside overnight. At freezing temperatures in the winter, the condensation turns into frost or ice, which might require some scraping away by hand using an ice scraper on top of some thawing by the defroster.

The Quickest Way To Defrost Your Car With The Defroster (1)

It’s important to note that your car’s defroster works hand in hand with the air conditioning system to deal with fogging or frosting on the glass. In both the hot or cold settings, your air conditioner condenses the moisture in the air into tiny water droplets. This condensation is vented through a drain hose that runs from behind your glove box and dispensed outside from the bottom of the car. The system then supplies new dry air into the cabin. When you turn on the defroster, it pumps dry air up toward the windshield to quickly evaporate the moisture around this area and effectively defrost the windshield.

(Video) How to Defrost Car Windows

What this means is using the defroster together with the A/C is the quickest way to defrost your windshield. But it also means that if your air conditioner isn’t working properly, you won’t be getting optimal performance from your defroster either, and it may only clear the moisture from the glass slightly.

You will learn the proper steps to most effectively defrost or defog your windows and windshield further down below. In general, as above, the defroster is used hand in hand with the A/C for defogging, but you may notice that cold air works better during the summer and warm air works better during the winter, depending on the temperature difference between the outside ambient air and your car’s interior air.

In addition to drying the humidity from the air, your defroster also serves to equalize the temperature of the glass and the temperature of the air inside the vehicle to some extent.

Front Defroster and Rear Defroster: How They Work

The majority of older cars only have the front defrosters on the windshield. This might not be very helpful in terms of visibility if the rest of your windows are all fogged up. Fortunately, many newer models also pack rear defrosters on the rear window as well to quickly restore visibility.

Front defroster

(Video) How to Defog Car Windows FAST (DRIVING TEST TIPS)

The front defroster works a little differently than the rear units. The front defroster has vents on the dashboard that face the windshield and front windows. When you turn on the front defroster, air will be circulated through these vents and directed toward the windshield and front windows to defrost the windows. This air is circulated thanks to the fan and blower motor that operates the heating and air conditioning system. This is why we said earlier that your defroster is tied into your A/C system.

To engage the front defroster, you just need to turn on the fan and turn the setting to defrost, while making sure the vents are open and then adjust the temperature to your desired level.

When you engage the front defroster, the coolant will reach a certain temperature to open the thermostat. Hot water will move through the heater’s core to heat up the air, then the blower fan will blow the warm air through the vents of the defroster and directly onto the windshield and front windows. The glass will warm up, and as it reaches the desired temperature, the condensation or frost will begin to dissipate.

In addition to removing condensation and ice on the outside of the glass, the front defroster can also remove fog on the inside of the glass. Condensation in the interior often occurs when the air outside is cooler than the air inside.

While the rear defroster will begin removing the condensation immediately upon activation, the front defrost with the fan and blower must wait until the temperature of the vehicle warms up to the desired level for it to defog or defrost effectively.

(Video) How to Use Your Windshield Wipers And Defroster In a Car Driving Tutorial

Rear defroster

For most newer vehicles today, the rear defroster is electric and has its own button for separate access when you want to defrost the rear window. The rear window will have thin black lines running horizontally across it, which are electrical. When the rear defroster is activated, these electrical lines will heat up and thus you will notice the condensation or frost dissipating first along the lines until the entire window is clear.

These heated electrical lines only provide a low amount of heat enough to defrost ice and won’t burn you if you touch the window while they are activated.

One huge advantage of such an electric rear defrost system is that it begins working very quickly as soon as you turn the vehicle on and hit the rear defrost button. That is why many newer vehicles are including electric defroster along the edges of the front windshield on top of the front defroster to remove condensation faster.

Side view mirrors defroster

(Video) How to Defrost Car Windows in 1 minute (-10°C) | Ice Windshield

The side view exterior mirrors also use electrical defrosters like those on the rear windows to remove condensation and frost in the winter for battery visibility, but you won’t see visible thin black lines as with the rear window defroster.

READ MORE

  • How To Clean Car Windows Without Streaks
  • Best Ways To Clean Bugs Off Windshield

The Quickest Way To Defrost Your Windows and Windshield

  • Turn your heater on: As above, warmer air can suspend more moisture. If the air in your car holds a lot of moisture, then it will condense as tiny water droplets on the windows and windshield on cooler days, as the glass surface is colder and thus the air on its surface is colder than the air in the cabin. So the principle for dealing with cabin condensation must start with increasing the temperature inside your car. Start your engine, activate the defroster setting, then crank the heater up all the way and direct warm air at your windshield and front windows to evaporate excess moisture on the glass.
  • Press the A/C button: Now after cranking up your heater, turning on the A/C may sound counterintuitive, but really what you’re doing is activating a setting on the air conditioning system that helps dry the interior air faster. You can defrost your car without using the A/C, but using the A/C together with the heater is actually the quickest way to defog and defrost your car effectively. The A/C will pull the moisture from the air as it passes over the cooling coils in your cooling system.
  • Turn on air recirculation in the winter: You need a new supply of fresh air to enter the cabin as well. Winter air is cold, which means it does not hold much moisture. Letting this dry air entering your car will help dry the saturated air inside more quickly.
  • Crack your windows just a little bit: Again, this helps the dryer outside air to enter and replace the humid air in your car, speeding up the defogging process.
  • Defrost windows with homemade de-icing solution: After you’ve performed the above steps to defog our windows, if there’s ice buildup on the exterior of the glass, you’ll need to defrost from the outside while the defroster and A/C is working. Contrary to what many folks expect, de-icing your windows never requires and should never involve hot or boiling water. You can use a plastic scraper with a brush at one end to remove the ice, but this can take forever.

For easy defrosting, mix a homemade de-icing solution of 2/3 cup Isopropyl or rubbing alcohol and 1/3 cup water and pour the mixture into a spray bottle. This solution will not freeze, since rubbing alcohol has a freezing point of 138 degrees below zero, and will allow you to easily spray away windshield ice. This also means that you can store this spray bottle in your car at all times during the winter for use.

To defog your windows and windshield when it’s not freezing but raining though, you won’t be able to crack the windows open. In this case, do this for quick defogging:

  • Turn on your A/C: Turn on the A/C for the cooling coils to remove moisture from the cabin air.
  • Turn off air recirculation: This is the number one mistake people make when trying to rapidly defog windows. When it’s raining, the air outside will have a lot of moisture, so you won’t want it to enter the cabin.

Common Reasons Your Defroster Is Not Working

If you find that your defroster is not working properly as per usual, inspect for the following issues and have them fixed:

(Video) This Weatherman Reveals The Secret To Defrosting Your Windshield In SECONDS

  • Lack of antifreeze: When there’s not enough antifreeze, the heater will not heat up properly and thus the defroster won’t be as effective in defrosting the windows.
  • Clogged defroster vent: When the front defroster’s vent is clogged with dust and debris, the warm air cannot blow through to heat up the windshield and front windows. A dirty vent will need to be cleaned.
  • Frayed wires: Wires that are loose or frayed will prevent the defroster from working and needs to be secured or replaced.
  • Blown fuse: An overloaded circuit might blow the fuse that connects to the defroster. The fuse will need to be tested and replaced by a professional.
  • Stuck or malfunctioning buttons or knobs: A stuck button might be repaired, but if it malfunctions, it may need replacement.
  • Missing terminal edges on the window: Tinted windows that have started cracking or tint that has come off can render the defrosting process less effective.

FAQs

How do you use defrost in a car? ›

HOW TO QUICKLY DEFOG THE WINDSHIELD
  1. Press the Defog/Defrost button. ...
  2. Turn off the Recirculation button if it's on.
  3. Press the Sync button (if equipped).
  4. Set the fan to the highest setting.
  5. If defrosting, set the temperature to High (automatic system) or Full Hot (manual system).
  6. If defogging, turn the A/C to On.

How do you defrost your windshield in less than a minute? ›

Simply mix 1/3 part water and 2/3 part isopropyl or rubbing alcohol. Pour the solution into a spray bottle, and in the morning, spray it on your windshield. The ice will disappear instantly!

Why does my car take forever to defrost? ›

If you're finding it takes a longer time than you'd expect, the culprit is often your cabin air filter. This is true for all models of vehicles. In order for the maximum amount of heat to pass from the engine compartment, through your vents, and onto the windshield, the system must be free from obstruction.

How do you defrost car windows with water? ›

Tote the bucket to your car and gradually pour the water over the frozen windshield, starting from the top left or right corner and working horizontally across the glass. As the warm water trickles down, it will immediately thaw the ice in its path, turning it into an opaque slush.

How do you defrost a windshield in hot weather? ›

Mastering the Defrost in Summer
  1. Let outside air in to balance out your car's temperature. We know it's hot outside, but letting the warm air outside come into your car to remedy this problem can be a quick fix. ...
  2. Use your windshield wipers. ...
  3. Use your defrost. ...
  4. Turn your air conditioning down. ...
  5. Drive with the windows down.
Aug 15, 2016

How do you use a front defroster? ›

How to Defrost Car Windows
  1. First, turn the front defogger on high. If your vehicle has a rear windshield defroster, you will want to turn on that car defroster as well.
  2. Turn the fan on high. ...
  3. Turn the temperature on high. ...
  4. Turn the air conditioning on. ...
  5. Turn off the recirculated air.

Which button is defrost? ›

To defrost or defog the windshield and door windows, slide the temperature lever to the right or turn the temperature control dial clockwise, select the (defrost) function, and switch the fan on. If there is actual frost on the windows, first select the posi- tion. If the windows are fogged, select to the setting.

Should defrost be on hot or cold? ›

The warm air from the defroster helps evaporate the moisture near the windshield, but it's only a temporary fix. If you want to stop the fog from forming, experts recommend using cool air to lower the temperature on the inside of the glass.

How do I stop my car windows from freezing? ›

5 winter car hacks to keep your car from freezing - YouTube

Can I pour cold water on my frozen windshield? ›

Never pour hot or warm water on your windshield to defrost it, as this can also cause the glass to crack. Pouring cold water is also a bad idea, as it can freeze on the glass and make matters worse. Once the ice has started to melt you can begin removing it with a scraper and brush.

How do I stop my car windows from fogging up? ›

Some of the best ways to prevent a foggy windshield include:
  1. Use an Ammonia-Based Window Cleaner. ...
  2. Apply Shaving Cream to Your Windshield's Interior. ...
  3. Activate the Defroster When You Warm Up Your Car. ...
  4. Use Fresh Air Mode. ...
  5. Keep a Car Window Open. ...
  6. Wipe Your Shoes Before You Enter Your Car. ...
  7. Get Your Car's HVAC System Inspected.
Jun 20, 2020

Can you put hot water on frozen windshield? ›

Answer: No. While it may be tempting to quickly thaw out your windshield with hot water, it's a very bad idea. Rapid temperature changes in glass can cause it to crack, and automotive glass is no exception.

How do you make a defrost spray? ›

Mix one part room temperature water and two parts 70% isopropyl (rubbing) alcohol in a spray bottle, writes Wisebread. Spray the outside of every car window before going to bed. In the morning, you'll have an easier time scraping off the frost. If you forgot to do it the night before, don't worry.

How do you defrost a car in the rain? ›

You can turn off the air recirculation function to allow the AC to draw some fresh air inside the car. You can also turn on the heater to quickly clear the fog. Lastly, you can also turn on the defogger as it blows hot air into the glass surface and quickly clears the fog.

Why do my car windows ice up inside? ›

Extreme cold temperatures can cause ice and fog to form on the inside of car windows when the moisture in the car evaporates, condenses on the glass and freezes. Other explanations can be from warm air being exhaled by car passengers, and any melting snow brought into the vehicle from boots and winter jackets.

What is the best temp to defrost windshield? ›

Fog is water condensation, and water condensation comes from air saturated in water vapor. Hot and dry air can hold much more water than cold and wet air, so the fastest way to defrost your windshield is to make the air around it as hot and dry as possible.

What does the defroster button look like? ›

Have you noticed that defroster button on your dashboard? It looks like a window with three arrows pointing upward. Make sure you press that so that the heated air targets the foggy windows. Also, some cars have a separate button for the rear defrosters.

How does the defroster work? ›

Windshield defrosters blow air from the heating and ventilation system onto the windshield through vents at the forward edge of the dashboard. Most vehicles have a setting for directing all air to the windshield for maximum defrosting or splitting the air between the windshield and floor level.

How do you open a frozen car window? ›

Rubbing Alcohol

Isopropyl (rubbing) alcohol is also a great option for breaking away pesky ice; you'll want to mix it in the same way as our listed vinegar compound (three-fourths cup of alcohol, one-fourths of room temperature water) and spray your window. Let this sit for around three minutes and repeat as necessary.

Which is the defrost symbol on a car? ›

The symbol for the front is a curved window, while the rear is rectangular. While you are defogging the windshield, you may not be able to get air out of the normal vents.

How do you get ice off car glass? ›

Rubbing Alcohol Solution: Highly recommended is the mixing of isopropyl (rubbing alcohol) and water. Mix two-thirds rubbing alcohol and one-third water and place into a spray bottle. Shake up the bottle, spray the solution on your windshield, and watch as the ice and frost disappears.

Should AC be on for defrost? ›

Step 1: Turn OFF your AC.

We know, we know: It's hot. But frozen AC parts are bad news for the most expensive piece of your HVAC unit—the compressor. To avoid lasting damage and a hefty bill, turn your thermostat from COOL to OFF. This will start the defrosting process.

Can I put a blanket on my windshield? ›

If it's a really wet snow and temperatures are projected to drop below zero, skip this tip—it may result in a frozen blanket to your windshield. However, if the temperatures are freezing, but with no snow, then throw a blanket over your windshield to keep it from frosting over during the night.

Does vinegar prevent ice on windshield? ›

AAA experts explained leaving the mixture on the glass is ineffective because it's freezing point is just barely lower than that of water, so not a substantial effect to make ice melt.

Does hand sanitizer melt ice? ›

Can't get your key in the lock? Look through your bag for hand sanitizer. The alcohol content here also lowers the freezing point of water and melts the ice inside the lock. Apply a few drops onto the key and gently work the gel in.

Does vinegar unfreeze car doors? ›

“To unfreeze your car doors, simply fill a spray bottle with two parts vinegar to one part water. Spray liberally on the doors, taking care to avoid your car's windows. The vinegar will melt the ice. And after about a minute, you should be able to open your car door.

Can I use salt to melt ice on my car? ›

Saltwater for your Car

Running late and you don't have a windshield scraper in the car? So try a saltwater mix. Road salt mixed with some water will remove the thin layer of ice when the temperature dips below 32 degrees F. And then use your wipers to push the slush away.

How do you remove fog from car glass in winter? ›

During winters, you can air out the fog by cranking up the windows in your car. Simultaneously, reduce the heat down to create equilibrium between the outdoor temperature and the temperature inside the car. This will eliminate the fog gradually.

Why do my car windows fog up on the inside when it rains? ›

Condensation happens on the windshield because of the high humidity inside the vehicle, and the fogging is because of the temperature outside is colder than inside your vehicle. Think of how moisture that gathers on the outside of your drink, this is the same scenario.

How do you keep ice off your windshield overnight? ›

Each night before you go to bed, spray your windshield down with a vinegar solution that is three parts vinegar and one part water. This vinegar solution will help prevent frost and ice from forming on your windshield and if you are in a hurry in the morning, the same mixture will melt the ice.

Can I pour boiling water on my car? ›

Hot water will crack windshield

"While it may be tempting to quickly thaw out your windshield with hot water, it's a very bad idea. Rapid temperature changes in glass can cause it to crack, and automotive glass is no exception," according to the site for the Glass Doctor a glass repair and replacement company.

Do you pour cold or hot water on a frozen windshield? ›

1. Pour hot water on the vehicle's windshield and windows to melt the ice. The frozen glass could shatter due to the extreme temperature change.

Do I defrost with hot or cold air? ›

For a quick fix: According to Road and Track, this is the fastest way to defog your windshield: First, turn the heat on its maximum setting, because hot air can hold more moisture. Then, turn the AC on, which will pull the moisture from the air as it passes over the cooling coils.

How long does it take to de ice a car? ›

It should be expected that your vehicle may take around 10-15 minutes to fully defrost, so don't try to rush the process as this could cause damage to your vehicle or unsafe driving.

How do you de ice your car without de icer? ›

We're not saying any of these are better than a can of deicer, but if you run out… needs must!
  1. Use warm water in a bag to defrost your car windscreen. ...
  2. Use an onion to stop your windscreen from freezing. ...
  3. Use toothpaste to prevent icy windows. ...
  4. Use potato juice to stop your windscreen freezing. ...
  5. Make your own deicer!
Dec 10, 2020

How do you melt snow faster in a car? ›

They include:
  1. Turning on your front and rear defrosters as soon as you start clearing. ...
  2. Give yourself more time than you think. ...
  3. Don't pull on frozen windshield wipers! ...
  4. Avoid hot water. ...
  5. Use a proper snow brush. ...
  6. Start from the top. ...
  7. Consider using a deicing spray. ...
  8. Blow through a straw to let your breath melt a frozen lock.
Jan 3, 2017

Why do my car windows ice up inside? ›

Extreme cold temperatures can cause ice and fog to form on the inside of car windows when the moisture in the car evaporates, condenses on the glass and freezes. Other explanations can be from warm air being exhaled by car passengers, and any melting snow brought into the vehicle from boots and winter jackets.

How do I keep my car windows from fogging up? ›

The first step in preventing automotive fog is to give your vehicle's windows and windshield a nice wipe down. Dirt and oils on the glass will attract and maintain condensation. Clean your car's windows/windshield on both sides with some window cleaner and a newspaper or paper towel. Apply an anti-fog spray.

How long does it take to defrost ice on car? ›

The first step to properly defrosting your windshield is getting into your vehicle and turning it on. Then, turning on your heating to the “defrost” setting, and waiting 5 minutes to 15 minutes for your windshield to warm up and begin to defrost.

Will pouring warm water on frozen windshield? ›

Hot water will crack windshield

Pouring hot water on your vehicle's windshield to melt the ice could actually crack or shatter the glass due to extreme temperature changes. "While it may be tempting to quickly thaw out your windshield with hot water, it's a very bad idea.

Can I use water to de-ice my car? ›

You can buy eco-friendly de-icers, but if you want to be even greener, a homemade de-icer might be the best option. Make a solution using water and a teaspoon of salt. You can then use a misting spray bottle to spray it on the windscreen, or wipe it on with an old towel. Don't overuse it, though.

Does putting a towel on windshield to prevent frost? ›

You can prevent frost and ice from forming on your windshield by placing a dry towel on your windshield overnight. Ice will form on top of the towel, not your windshield. In the morning, remove the towel, and you will have a clear, ice-free windshield beneath.

Can I pour cold water on my frozen windshield? ›

Never pour hot or warm water on your windshield to defrost it, as this can also cause the glass to crack. Pouring cold water is also a bad idea, as it can freeze on the glass and make matters worse. Once the ice has started to melt you can begin removing it with a scraper and brush.

What works as a deicer? ›

Mix equal amounts of vinegar and water to produce an effective deicer. If the ice is very thick combine 40 percent water and 60 percent vinegar, e.g., 4 cups of water to 6 cups of vinegar; or 8 cups water to 12 cups vinegar. Pour the mixture on iced surfaces and ice will slowly turn to liquid.

What melts ice off windshield? ›

There are a couple of different solutions that will help melt the ice on your car faster. Mix together (don't shake) rubbing alcohol and dish soap for one, try 3 parts white vinegar and one-part water or even 1/3 a cup of water and 2/3 cup of rubbing alcohol. These concoctions should have you on your way in no time!

Can you pour hot water on car to melt snow? ›

Do Not Use Hot Water. Pouring hot water over snow and ice may seem like a great idea, but it can actually do some harm. The windshield's glass may crack from the extreme temperature change, leaving you with glass shards everywhere and puddles of water all over the ground, which can be its own hazard.

Can I use salt to melt ice on my car? ›

Saltwater for your Car

Running late and you don't have a windshield scraper in the car? So try a saltwater mix. Road salt mixed with some water will remove the thin layer of ice when the temperature dips below 32 degrees F. And then use your wipers to push the slush away.

Videos

1. Defog your windows TWICE as fast using SCIENCE- 4 easy steps
(Mark Rober)
2. How To Make A Homemade De-Icer Spray/DeFrost Your Car | Cheap With Results
(ZRK REVIEWS)
3. Defrost Your Windshield The Easy Way - Using a Space Heater!
(chasiu75)
4. How to Defog Car Windows Fast!
(breakaway2x)
5. HOW TO DEFOG CAR WINDOWS SUPER FAST !!
(Pan The Organizer)
6. DEFROST WINDSHIELD - HOW TO
(DIY Pinto)

Top Articles

Latest Posts

Article information

Author: Kimberely Baumbach CPA

Last Updated: 12/25/2022

Views: 6248

Rating: 4 / 5 (61 voted)

Reviews: 84% of readers found this page helpful

Author information

Name: Kimberely Baumbach CPA

Birthday: 1996-01-14

Address: 8381 Boyce Course, Imeldachester, ND 74681

Phone: +3571286597580

Job: Product Banking Analyst

Hobby: Cosplaying, Inline skating, Amateur radio, Baton twirling, Mountaineering, Flying, Archery

Introduction: My name is Kimberely Baumbach CPA, I am a gorgeous, bright, charming, encouraging, zealous, lively, good person who loves writing and wants to share my knowledge and understanding with you.