heater matrix replacement with Diavia aircon!?!

[Purplebaghera 0]

Hi. been trying to read up on all threads regarding this job,but have not been able to find anything in relation to any further complications involved if your corrado has Diavia air con! does anyone know of any? also if the matrix has gone and has been by-passed, does that mean the aircon will not work? (obviously it did before the matrix went.) sorry i'm probably sounding a bit dense now,and theres an obvious reason why it doesn't work now. Thanks for any advice on this ,as I will be attemting it in the next couple of weeks. Cheers. Purplebaghera.

[Bruno 4]

Got it in one. However the heater matrix is not unique to Diavia - its almost the same as a Golf a/c matrix, and that one should fit. MIne is an original corrado one, and the matrix went two years ago. OEM one needed to be hunted down, but worked fine. After that you need to check the brushes on the blower and replace them if needed, check the internal temp probe and make sure it hasnt been stuck in the wrong place. The relays at the front need to be cleaned up, etc. The system then may need filling up and the dryer sorting (if it was allowed to empty completely).

[Purplebaghera 0]

Hi. Bruno. Thanks for reply, just to clarify, are you saying that the matrix is different from standard non aircon? or only possibly , as I think you are saying that when yours went it was a standard one? should I go for the golf one? Where is the internal temp probe and how do I know if its in the wrong place? So if the matrix fails does the aircon dump all its gas? Can any of these questions be answered if I print out the Diavia Aircon thread/ Sorry to bombard you with all this,don't know too much about aircon yet,but I am an engineer so cant be to difficult? Cheers Purplebaghera.

[fla 9]

the internal temp probe runs behind the centre part of te main console. If you find the probe thermostat (the black knob on the side of the pass side lower glove box, just trace this back and that's your probe. Sorry, dont know about the rest.

[Purplebaghera 0]

Thanks Fla. I'll piece all this together eventually :D Someone out there must have done this? or know of a thread that details it. thanks in anticipation. Purplebaghera.

[markrtw 0]

Hi, I have the Davia air con and I have replaced the matrix and I have also replaced a matrix on a friends VR6 without aircon. Just get a mk3 golf valeo matrix (forgive my spelling) from German and Swedish as it's the same as the one you will get from a dealer (it comes with a foam bit you stick on it when fitting and a little white bit of plastic that you spend the whole job trying to figure out what its for and then throw away). Thats all you need in parts as far as I remember.

You will have to take the whole dash out (that you don't have to do without aircon) which is quite a ball ache and then detach the main air box/heater matrix housing (the bit behind the centre console) from the air intake piping that comes from the blower fan and the matrix thing for the air con (the area in front of the passenger thats hidden behind the shelf under the glovebox). It's fairly obvious once the dashboard is out. I cannot remember if the instructions I followed were printed from the wiki or if I just searched for it. Some of the dash bolts are tucked up in the bulkhead in the engine bay and are a pain to find, so a guide to find them is helpful.

I did it in a (long) day. It's not difficult, but it is time consuming getting the dash out and back in and reconnecting everything. I would suggest using some masking tape and labeling the wiring as you disconnect everything to make life a little easier when rebuilding it and just be methodical and don't rush it. It also gives you the chance to tidy up any wiring (if needed) and to secure everything down behind the dash to stop any rattles. When I did my friend's VR6, I took the chance to cut a bit out of the air ducting behind the stereo and plastic weld (soldering iron to melt it together) in some other bits of plastic to reseal it to allow more space for the stereo wiring.

 

Best of luck to you!

[Purplebaghera 0]

Thankyou very much.' markrtw' That was kinda what i was wanting to hear as regards whether I had to do the 'full dash out' job or not (can't say I'm looking forward to that),and that I need the golf matrix. Do all mk3 golf use the same matrix or do I have to get a proper aircon one? I kinda feel confident enough to have a go :) Did your friends aircon need anythimg else doing to it after the matrix change for it to work again? Where abouts in Bucks are you, might bump into or have already bumped into you at some point. I am near Great Missenden and have an Ice grey violet vr6 and a blackberry 16v. Best regards.' Purplebaghera'.

[markrtw 0]

Hello, The heater matrix is std across the golf range - there is no difference for air con as the 2 sytems are not linked except by the air ducting. I think the thing to do is fix the heating and then look at the air con. As long as the blower fan is operating on speed one, then the air con should work. If the air con does not click in at all that would point to a fuse or low gas pressure in the system or if the blower does not work on speed one, then there may be an issue with the blower speed resister and the aircon takes a live feed from it.

 

It was my one that has the aircon and it didn't work at the time anyway, I spend ages trying to understand the air con system and how it intergrates with the the car's electrics until I found out what was wrong with it. But it's perfect now! The best way to describe the air con system in the blower ducting is that the main heater matrix is mounted in the middle of the dash in the big box behind the centre console and there is an aircon cold matrix upstream of it about halfway down the blower tubing directly in front of the passenger seat. The systems do not touch. The aircon matrix is either on or off and the heater matrix is always on, but air either passes through it or bypasses it depending on the position of the airbox flaps which are positioned by the heater controls on the dash (hence its a good idea to lube the cables when the dash is out). So you can have the aircon on and still heat the air which is useful in winter for quick window demisting as aircon dehumidifys the air.

 

I'm at the top end of the county in the little town of Buckingham and work over the border in Oxfordshire, but if I'm ever down your way I'll keep an eye out for you. :salute:

[Purplebaghera 0]

Thanks again for all the info! I guess my next move is to get the matrix and wait for some sunny weather :lol: I'll let you know how i got on,and keep an eye out for ya if i'm up your way. take care. Vince. (Purplebaghera)