Should the V90 Air conditioning light be permanently on?

[martin calva]

This morning, I noticed that the blue light surrounding the air conditioning button on my V90 is lit up, whether or not the button is pushed in.

I have never noticed this before but am inclined to think that it was normally only lit up when the air-con button is pushed in to activate the air conditioning.

Q: Should the air-con button be lit up blue continually or only when the button is pushed in?

Q: If the latter, what should I check? I have the V90 book of electrical diagrams but it is not very helpful, just showing the control unit incorporating the button as a black box.

Many thanks for any help and suggestions.

[jonnyf90]

It will always be on if the selector is turned to de-mist (windows with 3 arrows).

Cheers

[martin calva]

Originally Posted by jonnyf90

It will always be on if the selector is turned to de-mist (windows with 3 arrows).

Cheers

jonnyf90 - Thank you so much. You hit the nail on the head. It never occurred to me that the system would have the intelligence to switch the air-con on even when the button had not been pushed but when dehumidified air was needed.

I'd been assuming that, at least, the push button switch was stuck closed.

Cheers!
Martin

[jonnyf90]

Originally Posted by martin calva

jonnyf90 - Thank you so much. You hit the nail on the head. It never occurred to me that the system would have the intelligence to switch the air-con on even when the button had not been pushed but when dehumidified air was needed.

I'd been assuming that, at least, the push button switch was stuck closed.

Cheers!
Martin

I asked myself the very same question when I got my 960!
If you want to save fuel etc, the up/down arrow (screen/feet) provides equally good air to the windscreen without the AC on 👍

Cheers

[Laird Scooby]

Usually the only cause for alarm is when the light round the A/C button starts flashing - that indicates a fault.

Most A/C systems are set up so that when demist (to the screen usually) is selected, the A/C is automatically triggered to supply conditioned (dried) air to the screen, to provide faster, more effective, demisting. Often this also overrides the temperature setting and changes the temperature to maximum, again for maximum demist.

You may also find that on humid days, the system will switch the A/C on and off even when set at say 21 or 22 degrees. There is also a sunlight sensor (on the left hand dash top speaker grille on mine) which detects if the car has been parked in sunlight and this will force the system into maximum cooling for 5 minutes unless certain other conditions are met - can't remember them all but most are common sense.

Without getting in to the whole "to use or not use and open windows" debate about A/C, it's generally more economical to use the A/C and keep your windows closed than it is to drive along with the windows open because of increased drag. It also keeps the system working as it should as well.

[lynns hubby]

Without getting in to the whole "to use or not use and open windows" debate about A/C, it's generally more economical to use the A/C and keep your windows closed than it is to drive along with the windows open because of increased drag. It also keeps the system working as it should as well. [/QUOTE]

Whole heartedly agreed. I wish I could convince other members of my family!!!!
I was beginning to think I was the only one with this view.

[Laird Scooby]

Originally Posted by lynns hubby

Whole heartedly agreed. I wish I could convince other members of my family!!!!
I was beginning to think I was the only one with this view.

I've proven it countless times with my own cars and i'm sure i've seen scientific research online that also confirms it.

All that said, it's a little bit "horses for courses" - if you do a lot of town driving there's probably very little in it and opening the windows wouldn't help much as you'd be moving too slow for any real benefit. However the A/C will still pump out cold air even in town.

On the open road, the drag from an open window is certainly going to impact the fuel economy, a well-filled A/C system will definitely be more economical against that!

[MiniNinjaRob]

I read a good guide about the use of AC a while back and what I do is set off with all the windows down (easy in my 940 with all electric ones!) for a short distance with the AC on incoming fresh air. After 30s or so the air in the car is a degree or two cooler with fresh air in it so then I put the windows up and turn air con to re-circ until desired temperature is inside the cabin. I then turn it back to fresh air air-con as I don’t like the stale feel of re-circ.
This works well as on a hot day the temp in the car is always higher than outside with stale air so you may as well have the windows open for a short while to get the inside temp down to the outside temp and freshen things up a bit.