front defogger didn't work

Hi dbldbl,

I was out this morning when it was still 10 F outside. Front window was defogged (after exterior scraping, I park outside) in about 5 minutes. I do have 3/4's of my lower grill blocked.

This is allot better than the 2006 Prius I had. Where heat in the car took about 10 to 15 minutes in similar conditions, and 25 minutes without grill blocks in highway driving.

Did you clear your intake vents of snow? No dry air in from outside, no defrosted cold windows inside. And dehumidification by AC does not in cars work when the cabin is below freezing, as the cooling coils just gets clogged with frost. I imagine there are some high end cars, with a heater to reheat the cooling coils in such situations. But that is terribly wasteful, compared to clearing the outdoor cabin air intake.

 

Uh. This was prior to snow - at 1 F exterior temp by the Prius' thermocouple. And it's worse with snow about.

5 minutes - I should be at "work" within that 5 minutes. Hence, not yet cleared. Really disappointed. (I wont tell you how little time it takes a Volvo/VW/BMW/or Benz to clear out the front windshield.)

I'm trying to figure out if I use the remote AC start if that will pull the heat on too. The manual wasnt particularly forthcoming and the dealer was a total dip. (Only seemed to want my address and phone no. As it is, they forgot to activate the "OnStar" that is supposed to be a given for the 1st year. - and it's a Chicagoland dealer.)

After my German made car, I expect a certain Automatic with an AUTO mode.

Is this a hint that the Prius is intended only for heated blocks and warm climates?

 

It's been raining in LA so I finally used my windshield defrost.....

Pushing the front windshield defrost button automatically ramps up the fan speed, sets the vent position to defrost, gives you fresh air and activates A/C. Even if you turn off the A/C button after this has no effect as the A/C is still on. You can manually control the other settings through, like fan speed. It does it all for you.

When I hit defrost the other day my windshield defrosted in seconds ... but it wasn't frosted over from freezing temps. It was from my wet clothes in the car because of the rain.

After I was defogged I turned the fan speed down to minimum and continued to drive. After a while I just hit OFF as I didn't want to waste power on A/C..... After a little while I would start to fog up again so if I just hit the fan speed up one notch it would turn back onto low but without the full blast of pushing the defrost button.

If you want more A/C (for better drying) turn off ECO mode (switch to normal mode) as the A/C runs at a lower RPM in ECO mode.

- Turn on car
- Deactivate ECO mode (if enabled)
- Hit the windshield defrost button
- If fan doesn't come on right away (Due to cold coolant temp and a high heat setting on the control panel) manually turn the fan speed to max.

 

I have to say that, I too, find the front windshield defogging capabilities marginal at best. It is the vehicle's inability to keep the front window clear which was a primary impetus behind my installing a remote start. At least I can get the window warmed up before I get in the vehicle.

 

It's quite obvious that there is something not set correct with your controls........take a trip to your local dealer....let them straighten it out for you. It's not a everyday problem for many of us. Posting on PriusChat will not get your defroster working.

 

I don't think I've ever encountered more people who have so much trouble with a climate control system ... especially an automatic one. Mine functions perfectly, and as you would reasonably expect it to. I think the problems arise when people expect the impossible, in terms of time to defrost/heat, and start hacking around with the buttons like temp, fan speed, recirc button, and AC button, without ever having read the owner's manual or knowing what they're doing.

Here's what ya do ....

Press AUTO ... set the temp .... and WAIT. It's that simple. If your windows are fogged, press FRONT DEFROST ... and WAIT. If that doesn't work .... take the car to your dealer THEY'LL FIX IT if there's anything wrong. I'd be willing to bet that there's absolutely NOTHING wrong with any of these cars that are being complained about. I'd be interested in knowing how so many people get the INSIDE of their windows fogged ANYWAY. My guess is that it's improper use of the recirculate button. Unless of course, your clothes are wet or you have some other source of extreme humidity in your car.

The car (ALL cars) take(s) a while to warm up .... PERIOD. My climate control, when set to AUTO, won't start taking control and spin up the fan until the engine water temperature is at about 123 degrees. THAT is when the car has enough heat that the climate control can start doing something (at least for heating). Starting a car and letting it sit still idling will take forever to heat up the engine (or defrost your windows) ... you're better off driving it gently until the temp comes up if you can do so safely. My Prius, in 10-20 degree weather here in PA, takes about a half mile to come up to 123 degrees driven gently, which is about the same as EVERY OTHER CAR I've ever owned. The climate contol in these cars works wonderfully ... if you keep your paws off it and let it do what it needs to do ...

Even a Prius can't evercome the multiple dynamics of outdoor ambient temperature, physics, humidity, and thermodynamics .... IMMEDIATELY ... to say NOTHING of flailing users who expect the impossible from a stone cold car.

REV

 

I have never had this problem.

Have you guys put your hands in front off all the vents when you have it in defrost mode? Is all of the air going to the front windsheild? I'm wondering if their is a problem with your cars. When i hit the button it starts to blow harder and harder within seconds and most of the air goes to the front windshield and a little comes out of the other vents. but will defog it within seconds not minutes. But there is no frozen moisture on the inside of my windsheild.

I'm also wondering if the air in your car has alot of moisture in it when you shut it off at night then it floats up and sticks to the windsheild. What about running the floor vents on high speed with the ac button on to dry out the floor mats/ and the car on your drive home before you shut it off. I eould think if the car had dry air inside when you shut it off for the night, you couldn't have foggy windows in the morning.