Climatronic problem

[Blackdakdak]

Hi I'm having what seems to be a fairly common VW/Audi issue with my climatronic auto air blowing cold and fast when sunlight hits the front of the car - MY12 Tig 132. I tried some of the tricks others use like a piece of paper over the lump in the centre of the dash and amazingly it works! The fan speed drops and it works like it should, blowing air at the set temp, not freezing my head.

Just booked ut for the 30000k service and told service manager ( large newcastle nsw dealer) about the problem and that i thought the dash sensor needed adjustment. He told me the lump on the dash is purely ornamental and the is nothing, especially not a sensor under it.

Other dealer a bit further south told me Tig doesnt have a 'sunload sensor'.

So why does my fix work? Is it magic?

Astonishing that a $40k car needs the owner to find their own fix and use a sheet of white A4 paper, or shadecloth or window tint, as others use.

Anyone know a nsw dealer who will acknowledge and fix the problem?

[TobyJ82]

Can't say I knew there was a problem, but I have a MY12 155 and have thought that the climate control wasn't particular effective. Similar to you I find that quite often it's pumping in cold air even though I'll have the temp set 23 and it's much cooler than that outside.

Find that if it's cold outside, just end up having to turn the AC to off.

I don't recall if it was just during the day like in your scenario or if at night too.

Will be interested in any responses.

[Hillbilly]

The lump in the middle of the dash is normally the sensor for auto headlights. Find out by putting headlights on auto and check a book or a dark rag over it and see if lights come on

In a Passat the two vents across the top of the dash are the return vents for aircon so presume the sensor is under one of them

[Blackdakdak]

Thanks guys, That is exactly the same problem TobyJ.

I'll try a smaller bit of paper today and see if that isolates where the sensor is. Maybe it is in one of the front dash vents and my paper is covering it as well as the lump.

Other forums said the lump was for temp and the back of the mirror was for auto lights and auto wipers. I' ll see if the lump works the lights. The dealer telling me it did nothing is annoying.

I understand why a sunlight sensor would be used, but as other forums have suggested, it should be adjustable as to how much it lowers the temp when it thinks the hot sun is raising the internal temp. Aparently in audis there is a hot country and a standard setting to choose from.

[Hillbilly]

The rain sensing wiper activation is built in to the windscreen area that is darker in front of the mirror It will also activate if leaves or bits of rubbish hit it as it is pressure, not water that activates them. The auto dipping is in the back of the mirror.

[Blackdakdak]

Just tried auto headlights. They come on when the area on the back of the mirror stalk attached to the windscreen is covered. Waving your arm over this area also activates auto wipers. Covering the dashboard hump does not activate auto headlights, but something in that area adjusts the air speed and temp when you cover or uncover it. So dealer is at least partly wrong.

It makes sense. Hot dash behind glass - if there is a sensor there it will be reading the temp as hotter than the real cabin or outside temps are and then attempt to cool the cabin down.

Clever idea, but bad execution of it.

Mirror dipping is one if the holes in the front of the mirror. By front i mean the bit facing you. Light hits it from behind your car and it darkens.

[Dr freedom]

the front lump is a sunload sensor.. this is the case also for just about every car brand out there.
some of these dealers & their advice astonishes me

[Blackdakdak]

I suppose dealers arent really mechanics, just service techs and all they really want to do is quick expensive oil changes, not try and fix problems VW won't let them admit to. If their computer says there is no problem, they must be right!

When i take it in next week for the service i'll compliment the guy on the fantastic 'ornamental' hump on the dash and his half vast product knowledge.

[tigger73]

You could try installing a blob of blu-tak

[Blackdakdak]

Yeah blu-tack could work, especially applied to the rear end of the dealer, but i think i'll go with an offcut of window tint as it doesnt stand out as much as a sheet of white paper. I'll start with one layer and see how that works and add more if needed. I dont want to completely block the sensor, just calm it down a bit.