Skip the auto shop - Our mechanics make house calls

How Do Heated Windows Work?

Heated Window

The outside of your car’s windows are subject to harsh environmental elements including:

  • Stone chips
  • Road debris
  • Dirt
  • Bird droppings
  • Snow and ice

The benefits of heated windows

While you can’t prevent environmental elements from occurring, snow and ice can be combatted by heating the windows. Air blowing on the inside of the glass can be effective if the air is already warm, but it can take quite a while to heat up in freezing temperatures. Often, you won’t want to wait that long to begin driving.

Even if the temperature outside is above the freezing point, the inside of the windows can fog up from moist, humid weather conditions. Foggy windows obstruct your vision much like ice and snow on the windows can, making it unsafe to drive.

Nearly all back windows on cars and SUVs are equipped with heated windows, and some trucks are as well. 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.

Immovable side windows and power mirrors on some vehicles, as well as a select few windshields, are now equipped with an electrical grid of the same nature. While rear window defogger grids are usually visible as long horizontal lines on the glass, the side windows, windshield, and power mirrors use a very fine element that is barely visible at all, even on close inspection.

How heated windows work

Heated windows operate on a button or switch, and utilize a timer to turn the heat off after a certain period. Typically, it is between 10 and 15 minutes of operation.

The rear defogger will stop working if the grid is broken and is the most common problem for rear window defogger grids. If the rear window defogger has an electrical contact come off or a defogger line is scratched through, there will not be electrical continuity to heat the rear window. The grid can be repaired and electrical contacts can sometimes be re-secured.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
Veteran and Military Driver Laws and Benefits in New Mexico
The state of New Mexico offers a number of benefits and perks for those Americans who have either served in an Armed Forces branch...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...


Related questions

Q: My resr defroster is not working in my 2008 Dodge Caliber

Hello. Most of the time this is a problem with the TIPM> You would need a scan tool to see if there are any codes in the TIPM or to see if it is commanding the defroster to come on....

Q: Engine heating issue.

Hi there. From the description you provided, it would appear the engine does not have a head gasket problem from being overheated. If the temperature climbs above the middle point while the vehicle is at a stop it could be...

Q: Problems with driver's door

Hi there. A common cause of a window not going up is the window switch itself. Also a window that is off its track or a bad individual motor would cause this as well. As for your door not opening,...