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Does anyone else in the north have to keep the defrost on the highest setting constantly to keep the windows from fogging up? I'm in Northern MI and with it being single digits I have to keep it on high all the time. If I switch it to defrost and feet the windows fog up quickly, it's annoying.

 

Anyone else out there?

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My 2009 LGT struggles with that at times. I find running it on auto works the best. It chooses to run the a/c or not and I believe that is what takes the moisture out of the air and clears the windows.

 

Sent from my SM-G996U using Tapatalk

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My 2009 LGT struggles with that at times. I find running it on auto works the best. It chooses to run the a/c or not and I believe that is what takes the moisture out of the air and clears the windows.

 

Sent from my SM-G996U using Tapatalk

 

Good call, I'll try auto and see what happens.

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The AC switches off at low temperatures. Otherwise the evaporator can freeze. Thus defrost with AC doesn't work.

 

Interesting, I haven't experienced that. With the cars I had in WY, the A/C would still run to dry the air in sub-zero temps. If I manually turned off the A/C while on defrost, it would fog up again.

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You don't have the system in "recirculate" do you ? They will cause the windows to fog up.

 

Only use that setting for a few minutes to help warm up the inside quicker, then go back to mixing in outside fresh air.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

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My 2009 LGT struggles with that at times. I find running it on auto works the best. It chooses to run the a/c or not and I believe that is what takes the moisture out of the air and clears the windows.

 

Sent from my SM-G996U using Tapatalk

 

You don't have the system in "recirculate" do you ? They will cause the windows to fog up.

 

Only use that setting for a few minutes to help warm up the inside quicker, then go back to mixing in outside fresh air.

 

No it's taking in fresh air. It does kick the A/C on as well to dehumidify the thing, but as soon as I change it to any other setting the efficiency goes down the tubes and the windows fog quickly.

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Defrost works pretty quickly in colder temps for me (15-30F). Anything below that takes longer.

 

Is there excess moisture in the car? Possibly from melting snow on floor mats or a leak somewhere? I've had problems keeping windows defrosted in those situations. Filled a couple tube socks with silica cat litter and put them under the front seats to help absorb some of the extra moisture in the cabin that builds up during winter. They're like big "do not eat" desiccant packs. Cabin air filter clean? All HVAC actuators working correctly?

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Defrost works pretty quickly in colder temps for me (15-30F). Anything below that takes longer.

 

Is there excess moisture in the car? Possibly from melting snow on floor mats or a leak somewhere? I've had problems keeping windows defrosted in those situations. Filled a couple tube socks with silica cat litter and put them under the front seats to help absorb some of the extra moisture in the cabin that builds up during winter. They're like big "do not eat" desiccant packs. Cabin air filter clean? All HVAC actuators working correctly?

 

 

Everything seems to be working fine, but I can't say I've ever checked the cabin air filter, I don't even know where the dang thing is actually.

 

My floor mats (weathertech) do have a bit of snow/ice/water on the drivers side, which I should empty/clean out

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Next time you park the car on a sunny day, open the windows about an inch to let the car air out. I do that with my cars all the time.

 

See if that helps.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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Next time you park the car on a sunny day, open the windows about an inch to let the car air out. I do that with my cars all the time.

 

See if that helps.

 

 

I can't wait for those sunny days..... We're supposed to get 15-17" of snow over the next 48 hours...... I live in Upper Michigan, when it's sunny this time of year it means it's cold, like below zero cold.....

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Going to second the cabin air filter suggestion... There is no reason the defrosting wouldn't keep up even with melted snow in floor mats. If the filter hasn't been changed in a year it is clogged for sure.

2005 LGT Wagon Limited 6 MT RBP Stage 2 - 249K

2007 B9 Tribeca Limited DGM - 272K

SOLD - 2005 OB Limited 5 MT Silver - 245K

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The AC switches off at low temperatures. Otherwise the evaporator can freeze. Thus defrost with AC doesn't work.

 

I am quite sleep-deprived but am I reading this wrong? Defrost requires both heat as well as the A/C being on. It shouldn't freeze up unless set to below the minimum temperature granted by the climate control for a sustained period of time.

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AC runs during the defrost cycle to dry out incoming air (colder air contains less moisture). Air passes over the evaporator before the heater core. The heater core reheats the cool dry air before blowing it onto the windshield/side windows.

 

Is the evaporator even capable of getting cold enough to allow ice buildup? Granted it will be colder than the air coming out of the vents.

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AC runs during the defrost cycle to dry out incoming air (colder air contains less moisture). Air passes over the evaporator before the heater core. The heater core reheats the cool dry air before blowing it onto the windshield/side windows.

 

Is the evaporator even capable of getting cold enough to allow ice buildup? Granted it will be colder than the air coming out of the vents.

 

Many here have had an issue where the evaporator will freeze up if climate is set to 65 for extended periods of time.

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I generally need to use the max defrost when I have the whole family in the car and it's below -15°C. It gets significantly worse below -20°C and I need to keep max defrost on the whole time, instead of cycling it on and off.

 

Cabin air filter gets changed every September-ish after we are done driving gravel roads so it's pretty clean all winter. I have been using Wix filters which could be thicker than others.

 

Both cars (2005 and 2007) have the same issue at the same temperatures so I don't think it's a mechanical issue.

 

I should note that I thought my front windshield heater wasn't working due to having a crack running through the elements but I think it is a switch issue as I was able to turn it on today.

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So I changed the cabin air filter, it was dirty but not crazy. We will see how it goes, I haven't driven the car lately as we just got a ton of snow and my truck is far more comfortable (King Ranch for the win).

 

My windshield heater doesn't work currently either, I'm thinking it's a relay issue as the light on the button doesn't even light up, and the fuse is good, but I have to pull the panel down to get at the relay board.

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I can't wait for those sunny days..... We're supposed to get 15-17" of snow over the next 48 hours...... I live in Upper Michigan, when it's sunny this time of year it means it's cold, like below zero cold.....

 

My car is black so maybe that helps even this time of year. At work I'll park the car where it will get sun all day. open a couple of windows an inch. Haven't you noticed how warm the car interior is when the car is parked in the sun on a cold day ?

 

Even my silver 09 will be warm inside when parked in the sun this time of year.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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My car is black so maybe that helps even this time of year. At work I'll park the car where it will get sun all day. open a couple of windows an inch. Haven't you noticed how warm the car interior is when the car is parked in the sun on a cold day ?

 

Even my silver 09 will be warm inside when parked in the sun this time of year.

 

Yea I have noticed how warm it gets in there, even with 5% tint all around. I have to keep all the windows closed tight at work or it gets full of red dust (I work at an iron ore mine).

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Yea I have noticed how warm it gets in there, even with 5% tint all around. I have to keep all the windows closed tight at work or it gets full of red dust (I work at an iron ore mine).

 

Ok, then try it at home or when out shopping. The idea is to let the car vent out all the moisture. Doesn't matter where you do that...

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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