Hey All,

It is just starting to get real cold here in Chicago and lately I am having ice build up in either small or very large amounts in the inside of my windshield. I read that it could be from the snow coming onto the mats, but I keep them pretty dry.

I am going to ask the dealership to see if their might be some type of air leak or something. Any other suggestions? thanks

Wow, I've never encountered that in the winter before. You must have a good break in the windshield weatherstripping.

You know what, the other day I was taking off ice from the front of my windshield, and I knocked that strip thats right next to the windshield wipers and the actual windshield. It was really icy and I think I may have damaged it when getting the ice off the windshield.

I am going to ask the dealer to fix it...but Im not telling the dealer what I did! haha

if you park inside a heated garage this will happen.

I talked to the dealer and they are going to look at it for me this week, I will keep you updated with the answer.

I dont keep it in a garage, I just leave it outside. I have read if you have a lot of moisture on your feet, that it is possible for your car to do that on the inside. I tested it out last night by leaving the window cracked a little bit after it being very warm and no ice formed on it this morning....so I think the problem is on my end and not the car.

Because this car is awesome! So i doubt anything is wrong. haha

2009 2lt malibu, I keep it in a garage heated to 40 degrees, when about zero in the morning and take it out, I can watch Jack frost crawl from the top down about 1 inch every 15 seconds, kind of neat to watch it grow, then the engine warms up and defrost takes over and it crawls back the other way. Kind of the same issue? Must just be the shape or tilt of windshield.

On another note, what happens to the ice or moisture that is going to form on the sunroof??? where doe it go??? is there a drain on it??

I think it is probably from the moisture on the floor. It used to happen in my old car now and then. You get in the car and have the heat blowing on the floor. It melts the stuff off your feet onto/into the carpet and continues to warm. You get out of the car and the warm water in the carpet evaporates and then condenses and freezes on the cold windshield. You come out in the morning and see the ice all over the inside of the window. That would be my guess anyway.

Make sure you are NOT in recirculating mode with your vent system.

Also, turn on your AC which will remove moisture faster from the interior (but obviously keep the temp in the red zone!).

Make sure you are NOT in recirculating mode with your vent system.

Also, turn on your AC which will remove moisture faster from the interior (but obviously keep the temp in the red zone!).

The compressor will not turn on when the temperature is that low. When the system is in Defrost mode the compressor is turned on if the outside temp is high enough. Ice on the windshield is caused by a couple different factors. If it is real cold the moisture in your breath is enough to cause some icing on the inside of the windshield. The more people you have in th car the worse it can get. The other thing that can cause it is a light snow fall that gets snow into the inlet areas of the HVAC system. If there is no snow the best solution is to turn on the defroster with the blower set at max. If there is snow on the vent inlets clean the snow away as the defroster will suck it into the system and it will blow onto the windshield. As the heater core starts to warm up the snow evaporates and the moisture is blown on the cold windshield where it freezes. It will not reverse itself until the heater core gets very hot and it will take some time to melt the stuff off the windshield. I don't know of a car where this can be avoided unless it has an electrically heated windshield.

Bill

The compressor will not turn on when the temperature is that low. When the system is in Defrost mode the compressor is turned on if the outside temp is high enough. Ice on the windshield is caused by a couple different factors. If it is real cold the moisture in your breath is enough to cause some icing on the inside of the windshield. The more people you have in th car the worse it can get. The other thing that can cause it is a light snow fall that gets snow into the inlet areas of the HVAC system. If there is no snow the best solution is to turn on the defroster with the blower set at max. If there is snow on the vent inlets clean the snow away as the defroster will suck it into the system and it will blow onto the windshield. As the heater core starts to warm up the snow evaporates and the moisture is blown on the cold windshield where it freezes. It will not reverse itself until the heater core gets very hot and it will take some time to melt the stuff off the windshield. I don't know of a car where this can be avoided unless it has an electrically heated windshield.

Bill

Ive been able to do it with other cars Ive had, including our Honda Pilot and a Chev Equinox. In fact, I recall reading in owner's manuals that this is effective in removing inside moisture.

I havent had to use it in the Malibu so I'll take your word that the Malibu's system is different.

Ive been able to do it with other cars Ive had, including our Honda Pilot and a Chev Equinox. In fact, I recall reading in owner's manuals that this is effective in removing inside moisture.

I havent had to use it in the Malibu so I'll take your word that the Malibu's system is different.
you can run the AC compressor in freezing temps. i have an 09 malibu, and if you push the AC button, the compressor comes on. it also comes on when you turn th knob to defrost. they have done this for years, our 96 blazer, 96 lesabre, and 98 dodge all do this, its so that the compressor gets run, and lubricated so that it doesnt all dry up, and have a short life span, and ruin the seals from not being used all winter.

you can run the AC compressor in freezing temps. i have an 09 malibu, and if you push the AC button, the compressor comes on. it also comes on when you turn th knob to defrost. they have done this for years, our 96 blazer, 96 lesabre, and 98 dodge all do this, its so that the compressor gets run, and lubricated so that it doesnt all dry up, and have a short life span, and ruin the seals from not being used all winter.


Actually the AC compressor comes on with the defrost mode to control humidty inside the car, heat dries out air, with the AC compressor it keep the air humid enough so the windows don't fog up. Don't believe me, try this then, turn your heater on and hit the recirculate button then watch as the windows fog up cause of the drier air coming from the HVAC system then turn it to defrost, it should take it to fresh air on it's own and turn on the AC compressor. My Malibu, even though it's eight years old will not allow me to put the HVAC system on recirculate while in defrost mode.

Thanks for all the help and ideas everyone!

I had an appoitment for my dealer yesterday but decided to cancel based on the information from you guys. It turns out that I did not have the AC on and I also had it on recirculate all the time. I now turn the AC on and make sure not to have recirculate on.

Needless to say, there has not been a bit of ice anywhere on the inside of the windshield the past four days! I want to thank everyone for their help, this saved a lot of time :D

Thanks for all the help and ideas everyone!

I had an appoitment for my dealer yesterday but decided to cancel based on the information from you guys. It turns out that I did not have the AC on and I also had it on recirculate all the time. I now turn the AC on and make sure not to have recirculate on.

Needless to say, there has not been a bit of ice anywhere on the inside of the windshield the past four days! I want to thank everyone for their help, this saved a lot of time :D

Great that we could help!!

Recirc is great on initial start up in cold weather if you are not in the car because it reuses the interior air which generally is warmer and therefore heats up faster. Once you get in the car, switch it to fresh air to keep moisture (like your breath) from freezing on the windshield.

Thug-Had it happen to me today. It was about 7 degrees outside and had to drive to northern Ohio. When I had the heat set to dash and foot blower I got a 3 inch wide strip of ice on the inside of the windshield from the driver's side pillar to the middle of the windshield along the bottom. I did not have the recirculating air on. I switched to defrost and it went away. On the trip back I tried the same setting but it did not freeze up again.

Well thats good that it didnt freeze up again! Yesterday I was afraid that it was going to have a lot of ice because in Chicago it snowed a lot and it was extremely cold.. but none at all, these tips really helped out a lot

happend to mine today 2... between 0 and 5 degrees F

Glad I could help.

If you live in a cold climate, always start with the selector on defrost or heat/defrost until your car warms up and can heat your windshield.

Once it heats up, then you can switch the selector to vent etc.

If it fogs up, switch it back.

Also, if you have more than one person in the car and there's alot of talking, keep it on defrost all the time especially in this cold weather we are having.

Ive been able to do it with other cars Ive had, including our Honda Pilot and a Chev Equinox. In fact, I recall reading in owner's manuals that this is effective in removing inside moisture.

I havent had to use it in the Malibu so I'll take your word that the Malibu's system is different.

No car in the world will allow the compressor to run below a certain ambient temperature. That temperature is usually in the high 30s if you are using the Farenheit system. This is determined by the low side pressure in the A/C system. The low side pressure varies with temperature and when it falls below a set point (24-30 psi on GM cars) a switch opens the clutch on the compressor or on very old GM cars (earlier than the mid 70s) they would vary the pressure so the compressor never turned off. If they did not do this the evaporator would freeze over and the system would be clogged with ice.

Bill

No car in the world will allow the compressor to run below a certain ambient temperature. That temperature is usually in the high 30s if you are using the Farenheit system. This is determined by the low side pressure in the A/C system. The low side pressure varies with temperature and when it falls below a set point (24-30 psi on GM cars) a switch opens the clutch on the compressor or on very old GM cars (earlier than the mid 70s) they would vary the pressure so the compressor never turned off. If they did not do this the evaporator would freeze over and the system would be clogged with ice.

Bill

Maybe next time you got to drive your car on a cold day, pop the hood, have your HVAC system set on defrost and set the fan on medium or high, then stand outside the car and look at the AC compressor. You will see that it has kicked in, the system will work in cold weather. The system cycles off and on to keep it operating and to control the amount of humidity inside the car during the winter.

I get this ice too, but i park in a heated garage, it goes away when i turn my defroster on. I wipe the water away with a microfiber that I now keep in the car.

i recently washed got my car washed and when they were drying it, i noticed water beads on the inside of my rear window. maybe it was condensation or something, but it was about -1 degree out... any ideas?

Maybe next time you got to drive your car on a cold day, pop the hood, have your HVAC system set on defrost and set the fan on medium or high, then stand outside the car and look at the AC compressor. You will see that it has kicked in, the system will work in cold weather. The system cycles off and on to keep it operating and to control the amount of humidity inside the car during the winter.

I already knew my previous statement was correct but I waited until it was below freezing outside, the engine was warmed up and I turned on the defroster and made sure the AC button was lit. Then I opened the hood and watched the AC compressor clutch. Not once in 5 minutes did it turn on.

As I said before letting the evaporator freeze over is a bad thing. That is why automakers do not let it freeze over. I had a car where this happened and it wasn't pleasant to have the AC start spitting ice and slowly stop blowing air. That was in the summer time. Think how bad that would be when the temp is below freezing and you can't just shut the system off and let the ice melt.

The reason the defroster works in cold weather is the air can't hold as much water vapor and even the slight heating you get from the warming up coolant is enough to start drying the air.

Bill

I already knew my previous statement was correct but I waited until it was below freezing outside, the engine was warmed up and I turned on the defroster and made sure the AC button was lit. Then I opened the hood and watched the AC compressor clutch. Not once in 5 minutes did it turn on.

As I said before letting the evaporator freeze over is a bad thing. That is why automakers do not let it freeze over. I had a car where this happened and it wasn't pleasant to have the AC start spitting ice and slowly stop blowing air. That was in the summer time. Think how bad that would be when the temp is below freezing and you can't just shut the system off and let the ice melt.

The reason the defroster works in cold weather is the air can't hold as much water vapor and even the slight heating you get from the warming up coolant is enough to start drying the air.

Bill

I don't know where you get your information but I guess it takes all kinds. You don't turn the A/C on the defroster cycles the compressor off and on. and it will work with temperatures below 30 degrees. I surely know I'm not seeing things or hearing things when the compressor kicks off and on in defrost mode. Why is it working? Because HEAT DRIES AIR and cycling the compressor equalizes the humidity so the windows don't fog up. I've owned several GM and everyone of them will do this. See try just using the HEAT on the floor and watch the windows fog or ice up as some in here have complained about, let's see since the air is being dried inside the glass will collect moisture on the inside causing the windows to fog up. It works the opposite during the winter compared to summer, in the summer the A/C is drying the air inside the car whereas it's equalizing the humidity inside.

Just saw this posted by Bandit...

"GM Recalls Chevy Malibu Hybrids for Windshield Defroster Issue

General Motors Corp. is recalling 77 2009 Chevrolet Malibu hybrid vehicles for failing to comply with the requirements of the Federal Motor Vehicle Safety Standard No. 103, "Windshield Defrosting and Defogging System," according to a report from the National Traffic Highway Safety Administration (NHTSA). According to the report, the heating, ventilation and air-conditioning system may become inoperative, causing the blower to not function properly. If this were to occur, the manufacturer says the windshield might fog or frost and not be clearable.

The manufacturer warns vehicle owners to bring the vehicles to dealers, which will re-program the HVAC system. The recall began on December 17.

http://glassbytes.com/newsGM20090205.htm"

I am still having problems now and then with the ice building up within the windshield, but this only happens now and then. I am going to show this to my dealership and ask them. Does anyone think that this might not only affect the hybrids? I have a V6 2LT

This only applies to 77 out of the thousands of malibu hybrids

I doubt your 2LT would be covered by this recall.

I agree, I also wonder when this problem was occurring for the hybrids. Was this while driving, or while not being on. My problem occurs when it is not turned on, but this issue with the hybrids sounds like it occurs while driving. Just my opinion though.

I have owned 94 saturn, 95 sonoma, 03 sonoma, 01 grand am, 04 ion and now an 09 malibu. Every single one of the, when you turn on the defrost or defrost+dash vents the compressor has kicked on. On the older cars it ran constantly, on my last 2 trucks and on the malibu it runs on cycles, on off on off. Im also sure its normal for humidity control.

I agree, I also wonder when this problem was occurring for the hybrids. Was this while driving, or while not being on. My problem occurs when it is not turned on, but this issue with the hybrids sounds like it occurs while driving. Just my opinion though.


With what you've stated on what you are experiencing, it's because you are not turning the HVAC to defrost . If you put it on vent or floor heat the windows WILL fog and ice up every time. This proble the Hybrids are having is due to a malfunctioning HVAC system.

This happens to me when I open my coffee up while driving. It usually has to be really cold out for it to happen. a little humidity in the air and it fogs up the windows in no time.

I don't know where you get your information but I guess it takes all kinds. You don't turn the A/C on the defroster cycles the compressor off and on. and it will work with temperatures below 30 degrees. I surely know I'm not seeing things or hearing things when the compressor kicks off and on in defrost mode. Why is it working? Because HEAT DRIES AIR and cycling the compressor equalizes the humidity so the windows don't fog up. I've owned several GM and everyone of them will do this. See try just using the HEAT on the floor and watch the windows fog or ice up as some in here have complained about, let's see since the air is being dried inside the glass will collect moisture on the inside causing the windows to fog up. It works the opposite during the winter compared to summer, in the summer the A/C is drying the air inside the car whereas it's equalizing the humidity inside.

The defroster was on!!!! I get my info from the Service Manual and other documents relating to A/C service. You need to look into it yourself. They do not want the evaporator freezing over or the owner would be having a fit. That is why the turn off the compressor at temps in the high 30s. It doesn't take much to drop high humidity air in that range down to 32 degrees in the evaporator and when that happens ice is formed blocking air flow through the evaporator. When it is 30 to 33 degrees outside go out to your car and turn the defroster on and look at the compressor clutch (not the pulley) it will not be turning no matter how long you let the car run at that temp.

Here is a link to a video taken today with the temp at 32 degrees F, the defroster and A/C on and the compressor not turning.

http://s58.photobucket.com/albums/g270/BillD64/?action=view&current=_20090218_1507.flv

Bill

The defroster was on!!!! I get my info from the Service Manual and other documents relating to A/C service. You need to look into it yourself. They do not want the evaporator freezing over or the owner would be having a fit. That is why the turn off the compressor at temps in the high 30s. It doesn't take much to drop high humidity air in that range down to 32 degrees in the evaporator and when that happens ice is formed blocking air flow through the evaporator. When it is 30 to 33 degrees outside go out to your car and turn the defroster on and look at the compressor clutch (not the pulley) it will not be turning no matter how long you let the car run at that temp.

Here is a link to a video taken today with the temp at 32 degrees F, the defroster and A/C on and the compressor not turning.

http://s58.photobucket.com/albums/g270/BillD64/?action=view&current=_20090218_1507.flv

Bill

UH DID I SAY TO HAVE THE AC ON! NO I DID NOT IDIOT! The system works autonomously and does kick on the compressor in DEFROST MODE! I guess YOU NEED TO RE-READ what I WROTE!!! DUH! LOOK BACK AT WHAT I WROTE AND EXPLAINED ON HOW THE DEFROST SYSTEM WORKS!! PLAIN AND SIMPLE but I guess some JUST DON'T GET IT!

When the auto defog algorithm takes control of the
HVAC system, either of two type of control interactions
take place depending on the HVAC system component
being con-trolled. One is a direct override. The auto
defog algorithm dictates the operating state of the
component regardless of the commanded action from
the ACC system. For instance, in a fogging state, the
auto defog algorithm switches on the compressor and
opens the Air Inlet door to the outside air immediately to
enhance defogging capability.

Now can you read this which I've posted from a Delphi site! Hmmm, read what it states about how the HVAC system operates in DEFROST, in the LAST SENTENCE...

man this topic went from informative, to serious to just straight up reckless! lol

there is a drain in every moon roof. if it blocks you will notice it.

UH DID I SAY TO HAVE THE AC ON! NO I DID NOT IDIOT! The system works autonomously and does kick on the compressor in DEFROST MODE! I guess YOU NEED TO RE-READ what I WROTE!!! DUH! LOOK BACK AT WHAT I WROTE AND EXPLAINED ON HOW THE DEFROST SYSTEM WORKS!! PLAIN AND SIMPLE but I guess some JUST DON'T GET IT!

When the auto defog algorithm takes control of the
HVAC system, either of two type of control interactions
take place depending on the HVAC system component
being con-trolled. One is a direct override. The auto
defog algorithm dictates the operating state of the
component regardless of the commanded action from
the ACC system. For instance, in a fogging state, the
auto defog algorithm switches on the compressor and
opens the Air Inlet door to the outside air immediately to
enhance defogging capability.

Now can you read this which I've posted from a Delphi site! Hmmm, read what it states about how the HVAC system operates in DEFROST, in the LAST SENTENCE...

Ah, what can I say. Somebody who reads a statement that thinks it applies in all cases. Nobody is arguing that the compressor will never turn on when the defroster button is pushed only when it will cause evaporater freeze up. Then you make an issue over whether the AC button was pushed at the same time the system was in Defrost mode. You did see the button showing it was in Defrost mode didn't you. What you failed to notice is the compressor does not run even in Defrost mode. As they say you can lead a horse to water but you can't make him drink. I could have you standing by the car and go through every iteration you could think of and the compressor still wouldn't run but you would deny it.

Bill

some people aren't worth the waste of oxygen (or keystrokes) to argue with. let it go Glow - you could argue with bill to the death and he would still not understand.

some people aren't worth the waste of oxygen (or keystrokes) to argue with. let it go Glow - you could argue with bill to the death and he would still not understand.

Well it's becoming very OBVIOUS that Bill DOESN'T understand. I know exactly how the defrost portion of the HVAC system operates in the automobile, I've taken the time to understand how the complete auto HVAC system operates in AC and Defrost mode to understand why the system was designed to work that way. And there are only a few companies that make the HVAC systems that MOST manufacturers use in their automobiles. Delphi, which is owned or was owned by GM, builds these systems used in all GM vehicles.

Last blast to try and get you to see. Look at the video. Thirtytwo degrees, defrost selected, compressor not running. Today it was warmer outside so I tried the same test. Thirtyfive degrees, defrost selected in the exact same way as in the video, compressor running. What your little write up above didn't include was how it is impossible for a controller to override a mechanical on/off switch attached to the low side pressure sensor. The controller sends its signal to the compressor through that switch which opens when the pressure is below a set point. If you read AC service guides you will see that AC low side pressures map to the temperature of the refrigerant in the evaporator. No matter what the controller commands the compressor clutch to do the signal will not get through since the circuit is open.

Not everything is done with software. A computer is useless when it is disconnected from what it is controlling.

Have a good night. Goodbye.
Bill

Let's see, critque your video, you evidently HAD the AC ON, but you obviously DON'T UNDERSTAND. I guess it's hard to explain it to someone who doesn't understand. When I posted that information from Delphi's site it is the way the DEFROST works on all GM vehicles, as well as other makes, go you understand the basics of heating air and what happens to moisture? Then maybe you might figure it out on the way the DEFROST operates in these vehicles. Let's see heat dries air, which in an enclosed car will cause the windows to fog up or in extremes ice up, so to equalize the humidity within the car the defroster cycles the compressor, in other words with SIMPLE terms the system works opposite in defrost mode compared to AC mode, see AC in WARM weather removes the humidity in the air while COOLING it, whereas DEFROST equalizes the humidity inside the car, kind of like using a humidifier in your home. Now grasp onto the explaination.

Let's see, critque your video, you evidently HAD the AC ON, but you obviously DON'T UNDERSTAND. I guess it's hard to explain it to someone who doesn't understand. When I posted that information from Delphi's site it is the way the DEFROST works on all GM vehicles, as well as other makes, go you understand the basics of heating air and what happens to moisture? Then maybe you might figure it out on the way the DEFROST operates in these vehicles. Let's see heat dries air, which in an enclosed car will cause the windows to fog up or in extremes ice up, so to equalize the humidity within the car the defroster cycles the compressor, in other words with SIMPLE terms the system works opposite in defrost mode compared to AC mode, see AC in WARM weather removes the humidity in the air while COOLING it, whereas DEFROST equalizes the humidity inside the car, kind of like using a humidifier in your home. Now grasp onto the explaination.


Don't need to grasp it. I accept that you know everything about defrosting. Just don't try to tell it to an engineer designing the systems.

Bill