[anand_30]

I have a WagonR Vxi. Its supposed to come fitted with a de-fogger and fog lights. Its that time of the year now in Delhi when its at the foggiest best. So when I drive out, the windshield fogs up and I need to stop every 500 ms to wipe the windhield (inside) and use the wiper for the outside.

I switched on the in-built defogger - there was no effect (except for the red light glowing saying the defogger is working). So that's my question, what exactly is it working on - because I still can't see anything in front of me.

Someone told me, the defogger is for the rear window - helps take moisture off the back so I can see what's coming up behind. I somehow feel that's pretty dumb - I would want to look in front where I'm headed before looking back to see what's creeping up on me!

Which leads me to the next question, since the defogger is obviously not helping me, is there anything I can do to keep my windhield from fogging up? I like to drive with the windows all closed as it chills up if I keep it open, which is not very comfortable - to say the least. Any suggestions ?

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[ram.west]

Originally Posted by anand_30

I have a WagonR Vxi. Its supposed to come fitted with a de-fogger and fog lights. Its that time of the year now in Delhi when its at the foggiest best. So when I drive out, the windshield fogs up and I need to stop every 500 ms to wipe the windhield (inside) and use the wiper for the outside.

I switched on the in-built defogger - there was no effect (except for the red light glowing saying the defogger is working). So that's my question, what exactly is it working on - because I still can't see anything in front of me.

Someone told me, the defogger is for the rear window - helps take moisture off the back so I can see what's coming up behind. I somehow feel that's pretty dumb - I would want to look in front where I'm headed before looking back to see what's creeping up on me!

Which leads me to the next question, since the defogger is obviously not helping me, is there anything I can do to keep my windhield from fogging up? I like to drive with the windows all closed as it chills up if I keep it open, which is not very comfortable - to say the least. Any suggestions ?

Hey anand!!

Just put on your a/c buddy and your windshield will automatically de-mist!!! And as said the defoggers are for the rear windshield. !!


Cheers!!!

[anand_30]

Originally Posted by ram.west

Hey anand!!

Just put on your a/c buddy and your windshield will automatically de-mist!!! And as said the defoggers are for the rear windshield. !!


Cheers!!!

Yes thanks! I read all the 10 pages and confirmed the foggly layer was due to a temperature differential. I switched on the heater and directed it at the windscreen. Voila - no fog cheers:. However, the problem now is with the side view mirrors! The sides get all fogged up as well. I can't see anyone approaching or trying to overtake. Any solutions for that?

[ascertain]

I faced a really bad stretch with the windshield misting up frequently during the rains, and as I traveled with the A/C on at a bit on the warmer side- poof!- mist out of no where- and it just wouldn't go off ow much I wiped the inner aspect of the windshield. The side windows also had the same issue. I hunted around for any kind de-misting solution, and it was then that I chanced upon an internet article which said- If the outside of the windshield seems to be catching a mist early on - it could be because of a thin layer of oil & dust which must have settled. The author advised a thorough wiping of the glass with soap and water- and drying it.
With disbelief- I tried it- and presto- haven't had that problem since- now i do the routine every week.

The cleaning has to be intensive - WITH muscle work- not just spraying soap water over the glass and hosing it down.

[fabiarider]

Dear friends

My cars windscreen is having very poor visibility during rains. It looks more or less like full of stains on the glass. I tried cleaning it with some mild cleaning solution, but of no use. The peculiarity of the issue is that, this problem occurs only when there is rain(when water falls on windscreen). All other times its crystal clear. I fear if this are some fine scratches / stains of soap solution / or some other thing


Please help with your suggestions.

regards

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[S.H.Shankar]

Originally Posted by srijit

What causes fog to form outside the window? Wiper blade problems? How does one solve that, apart from stopping and wiping?

Srijit,

I had posted this somewhere I believe. Fog is condensation which occurs when warmer air meets cooler surface. So take the case of a car driving in the rain.

First, assume the car has no a/c. The rainwater falling on the windshield cools it down, where as the air inside the car is heated up by body heat and exhalation of the occupants. Hence when this hot air inside the car meets the (inside of) cold windscreen, condensation forms inside.

The other case is when the a/c is on and you have an a/c vent blowing on to the windscreen directly for long periods. In this case, the cold air from the a/c vent cools the windscreen to very low temperatures, less than that of the air outside. Now, when the cool air outside meets the even colder windscreen, condensation forms, outside. Hence the fogging as such is in no way related to the wiper blades.

However, the other effect commonly seen, and which doesn't seem to be related to the air-conditioning, is that the wiper blade leaves patches on the windsreen that scatter light from oncoming headlights. These patches can be seen to form immediately after the wiper blades pass across the windscreen, and then they dry off very quickly, only to form again when the blade passes over the screen the next time. This is not fogging, and is immediately recognizable as a different phenomenon. Fogging creates an even layer of condensation on the screen while this phenomenon causes patches on the screen somewhat like those on a leopard's coat.

I searched the net and located hundreds upon hundreds of pages about this phenomenon, but no convincing answer. I even saw this on a Jaguar users forum. Since I could get no conclusive information regarding the cause of, and remedy for, this phenomenon, I put up a query on the Toyota website. I had immediate response, they contacted me, fixed an appointment, checked the Innova at the workshop, etc. etc. but finally there was no solution to the issue. So until someone comes up with one....

[TRAUMASURG]

Originally Posted by raja748

Yes..that is windscreen defrost mode.As soon as rain starts I change AC setting to this mode,with internal air circulation ON.

I think the problem is turning on the recirculate mode ..try using it next time with recirculation off .i.e let outside air enter your cabin with a/c switched on ,the flow of air is directed toward the windshield...depending on the outside temperature you may need to turn the heater component as needed.the most important is do not turn the internal/ the cabin air circulation on...good luck

[fabiarider]

Originally Posted by S.H.Shankar

Srijit,


However, the other effect commonly seen, and which doesn't seem to be related to the air-conditioning, is that the wiper blade leaves patches on the windsreen that scatter light from oncoming headlights. These patches can be seen to form immediately after the wiper blades pass across the windscreen, and then they dry off very quickly, only to form again when the blade passes over the screen the next time. This is not fogging, and is immediately recognizable as a different phenomenon. Fogging creates an even layer of condensation on the screen while this phenomenon causes patches on the screen somewhat like those on a leopard's coat.

I searched the net and located hundreds upon hundreds of pages about this phenomenon, but no convincing answer. I even saw this on a Jaguar users forum. Since I could get no conclusive information regarding the cause of, and remedy for, this phenomenon, I put up a query on the Toyota website. I had immediate response, they contacted me, fixed an appointment, checked the Innova at the workshop, etc. etc. but finally there was no solution to the issue. So until someone comes up with one....

This is the same issue i am experiencing. May be the wiper has left hard to be seen fine patches on glass surface and water gets stuck in these cavities. The only reason for this to happen i think is when using wiper , sprayer mechanism to wipe of dust in windscreen. Generally i used to wipe of dust with a fine cloth but, a couple of times recently i used the wiper (being lazy ) and then it started.

[filcord]

.
:

Originally Posted by S.H.Shankar

Srijit,

However, the other effect commonly seen, and which doesn't seem to be related to the air-conditioning, is that the wiper blade leaves patches on the windsreen that scatter light from oncoming headlights. These patches can be seen to form immediately after the wiper blades pass across the windscreen, and then they dry off very quickly, only to form again when the blade passes over the screen the next time. This is not fogging, and is immediately recognizable as a different phenomenon. Fogging creates an even layer of condensation on the screen while this phenomenon causes patches on the screen somewhat like those on a leopard's coat.

Try this:
I faced the same problem years back, changed my wiper blades, washed the windscreen with Rain-X, all to no avail.

This phenom is caused by traffic grime and oil. Simply wash the outside of the windscreen with a strong detergent - Surf Excel, Henko, etc. rinse and wipe clean with a very clean (read - free of any oils or waxes) cloth. You should have no problem for the rest of the day, or until new traffic grime gets deposited.

For this reason I keep a small airtight jar filled with a strong detergent solution and a small cloth. One wipe with this, and presto!

[stefanm]

Originally Posted by sonirohit

Have you tried 3M Windshield anti-mist/anti-fog(Can't remember the exact name). I got it last weekend and have used it once. I see a difference. I am not sure about how effective it'll be during the monsoons/winters when this problem peaks
.

Where can you buy this stuff? have tried most of the local accessory shops to no avail, just blank looks, do the car dealers stock this?

[stefanm]

Surely someone can guide to where I can get this 3M anti mist defogger

[S.H.Shankar]

I believe filcord is right. Because I have recently noticed that I do not see the problem on days when I wash my car. Will try this out and revert.

[passion4cars]

Ok Guys I have the solution

- switch on the A/c
- direct the air towards the frontscreen
- move the a/c temperature setting towards HOT ( yes HOT )

and wait for 30seconds, i GUARANTEE you NO MIST or FOG type of build up on any windows ,

& yes i am not joking

[msaudf]

hey everybody,
this here is a common problem.
all you gotta do is keep the temperature in the car almost similar to the outside temperature, i mean, you'll have a rough idea right. and directing cold air from the aircon to the windscreen chills the windscreen and helps clear heavy fogging on the inside, but if used excessively it causes condensation on the outside of the windscreen leading to fogging after the windscreen wiper runs along. so, its best you leave the aircon in the normal position of airflow and air intake, but keep the temperature a bit warmer than you require but not warmer than outside.

and always keep your windscreen clean and wax free. any kind of oil film causes fogging.
drive safe.
Cheers.

[santosh.s]

Originally Posted by msaudf

hey everybody,
but keep the temperature a bit warmer than you require but not warmer than outside.

Can you please explain why? What is the logic behind that?