Heater Controls

[bmwcompact 10]

Recognising that this forum is a source of info on faults/repairs for Corrado owners I would like to add to what's already been said in the Forum Wiki on repairing/replacing heater controls. If you are not interested in doing this you may wish to read no further. If you are, you need to read /reread the wiki or you might not follow this post!

 

http://wiki.the-corrado.net/late_heater_control_repair.html

 

I have a 93 year build 2l 16v with 137K. The heater matrix was apparently replaced 6 years (10K miles ago) so I wasn't the first to delve here!

 

Like many owners, I found on purchase of my C, an inability to direct air to cabin/footwell/demist. I thought I'd have to live with this after reading posts on the forum and assumed my control unit was shot and was expensive to fix.

 

I spotted a new unit for sale, described as Golf 3, but clearly early 90s Passat (358 819 045) and therefore suitable for mod to fit the C (as outlined in forum Wiki). I negotiated a price and on receipt found the unit to have a date 22 FEB 1990-it was new but it appeared someone had tried to fit it to a car (Golf 3 ?) as it had marks where the Bowden cable clips fit.

 

I removed the centre console to access the control unit. There were problems with 2 screws accessed after pulling out the 2 top vents-you need a right angle crosspoint screwdiver. My control unit had 2 broken tabs, and the right hand (flow direction) mechanism was a scene of destruction-see photo on left. Specifically the main wheel which drives 2 levers was broken on the underside track (photo), its point of rotation on the base of the unit was broken off (photo), the V shaped metal clip shown in the photo was dislodged and the plastic holding it in place broken (photo shows it laying on the middle wheel). The mounting location for the Bowden cable of the top lever on the right wheel was broken and the cable attached with a cable tiewrap (not shown).

 

There were no problems with the Bowden cables: when they were operated, the flaps moved without difficulty.

 

Those who have found an adhesive that they believe bonds plastic successfully may have had a chance to effect some repair here!! I'm mostly a non believer.

 

Having acquired the new Passat unit, I set about modifying it in accordance with the procedure found on the Forum Wiki. No one has stated that patience is required to dismantle/modify/reassemble the unit. Those not in possession of this faculty may find that after several hours they have a heap of plastic scrap-they've attacked it with a hammer in frustration! I found several watchmakers flat bladed screwdrivers helped in separating the front part of the control from the gear wheel behind. (Removal of the dial knob is easy-its separating the actual control from the wheel behind that's difficult). The photo (right) shows the modified Passat unit. The removed parts in the foreground are: the rotating dial with copper contact which has to be changed for the one from the C, the centre front plastic dial and the metal arm previously behind the fan speed dial ). On reassembly you have to fiddle with the angular position of the fan speed front dial relative to the rear helical wheel to get the control knob position right. The V shaped clip on the right side was removed as per the Wiki procedure.

 

The Wiki stated you need to change the fan speed rear helical wheel-thats not so-they meant the front part with copper contacts as stated above.

 

I had a missing Bowden cable fixing clip (where the tiewrap was used) but found someone selling them on Ebay.

 

Its all together now and working the way it was on leaving the factory: long may it remain so.

 

I can only echo the words of those who have gone before me: its the biggest load of crap VW have ever designed/manufactured. How could they make this out of plastic/expect it to survive and charge so much for a replacement?

 

Edit: the eagle eyed among you may have spotted (right photo) that the clear plastic 'spider' sending light to the dials isn' t correctly located -it should be in the centre of the left helical gear. I did rectify before fitting!

 

 

[ATTACH=CONFIG]71996[/ATTACH][ATTACH=CONFIG]71999[/ATTACH]

Edited March 13, 2013 by bmwcompact

[James. 9]

Good work Alan. I'm sure if the Wiki pointed out all the patience required to get most jobs done on a Corrado, they'd have all been broken for parts by now !

 

A good reference for (hopefully) the distant future.

[Jim 2]

Always admire those users who take the time to do things like this, and then write up their experiences for others. Good work mate :)

[Talltorrac 10]

Hi

 

I am considering on embarking on this journey in your footsteps with my heater controls. I haven't actually fiddled, fettled or removed and poked the three offending dials yet to make sure they are definitely in need of replacement/repair, but all three need varying levels of fonz technique when being used!!

 

I ave two questions:-

1:My stumbling block and the first bit I need advice with, is what to replace them with; some discussions suggest the Golf MK3 set and some the Passat set, both of which have the dials in a different order which sparks my second question

2:does the order of the dials matter - are the mechanisms interchangeable into the 'rado faceplate? Or am I simply being a bit dim in that respect?

 

I'd appreciate some advice - not being able keep my fair lady warm and enabling her to see is not helping to convince of why I love my car so much (I can't use the glorious engine note and acceleration as a selling point -that would just get me a scowl)

[bmwcompact 10]

The Passat set I used (I think it was fitted 90-93) had the dials in the same place as the Corrado and used the same plastic chassis: it had additional/different parts added for each model. As I described above it was a case of modifying the passat controls to corrado spec.

 

The Golf 3 controls do have the dials in different positions. It can't have the same chassis as the corrado/Passat as this chassis is not symmetrical: you couldn't swap the mechanisms for dials 1 and 3 on the corrado/passat chassis. Without trawling to see whether others have used the golf control unit I dont know whether its possible to adapt this.

 

Some people simply have issues with the bowden cables/ heater flaps which may need lubricating. If its the controls it could be the cable attachment points have broken off, or the V shaped spring has become detached/the cog has broken as was the case with my controls.

 

I would like to reiterate how easy it is to break the tabs on the centre console/heater control and the attachment points for the cables. Since its usually the flow directional control that's broken, an easy fallback fix is to abandon the control dial and manually/permanently adjust the flaps for flow to the screen etc. This doesn't require the removal of the centre console /controls

 

If you have issues with fan speed, its usually not the control but the heater fan resister thats the problem.

 

In case you didnt find the Wiki post on this, Ive edited my original post above to add the link and also inserted it here.

 

http://wiki.the-corrado.net/late_heater_control_repair.html

Edited March 13, 2013 by bmwcompact

[Talltorrac 10]

Thanks for that.

 

Yours was the first bit of information I had found that used the passat dials. I'm hoping it will be as easy as lubrication but your description is certainly clear enough for me to follow should it be more than that. Just got to get hold of the dials now!

 

The fan speed is not an issue, just isn't effective on clearing the passenger side of the screen or heating the footwells - dash vents do work. A previous owner appears to have discovered the fragility of the dash tabs and surround!

 

Thanks again - hopefully I will get through this with all tabs fingers vents and thumbs!!