Heater working on few settings..

[OrangeCorradoVR6 10]

Hello all, right here's the problem, the heater in my Corrado only works on settings 3,4 and also in between 1&2 but it shuts off when clicked on to the setting of 1 or 2.

I did the heater matrix a while ago as I bought it and the seller never told me about it being knackered so I just did it soon after buying it, but I do remember that the heater did not work on either setting when I drove it up so it wasn't to do with the controls I don't think as I ensured they were all properly connected when the dashboard was out. Its never really bothered me though as its never nice enough weather to drive it (only did 800 miles from April last year up until now :/) and when it is nice weather you don't need the heater as its not cold enough for it. But I'm just wondering if it can be fixed without me having to remove the dash again.

I've had a look through the site and can't seem to find anyone with the same problem, there's the heater not working on the 4th setting problem but I haven't saw this one appear yet. It is a late style dash with the rotating controls.

 

Can anyone give me any advice on the problem?

Thanks.

[dragon 0]

Mine only worked on speed 4 and It was a cheep easy fix , could be worth trying it . if you already have a soldering iron it only costs 89p for a new resistor from maplins and around 10-15 mins of your time. I will try and find the guide for you that I followed

 

---------- Post added at 8:19 PM ---------- Previous post was at 8:16 PM ----------

 

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

[OrangeCorradoVR6 10]

That's great, i'll give it a go, thank you.

[seanl82 23]

Take the controls out and check the brass contacts at the rear of the dial itself. They are getting old, and as they're spring contacts they can loose their springyness! A bit of gentle persuasion with a small flathead May well do the trick!

[Henny 0]

if your fan works on any speed other than 4 (even only occasionally!) then it's not the thermal resistor that dragon mentions...

 

Most likely to be either the switch itself, or possibly the wiring from the switch to the thermal pack on the fan motor... :)

[OrangeCorradoVR6 10]

Ah right ok, I wont give the thermal resistor a go as the wiring/control contacts/ the switch itself being knackered, seem to be better reasons for it not to be working then even if it may be more difficult! I'll take the controls about and have a look about.

Thank you all :D

[Critical_Mass 10]

What if it works on all speeds apart from speed 1?

[Henny 0]

critical_mass in that case, you've either got a broken wire/switch, a broken resistor pack, or a dodgy fan motor that has shafted bearings meaning that the lower voltage that speed 1 gives to the motor isn't enough for the motor to overcome the friction of its bearings... Take the resistor pack off the motor, reconnect it to the wiring and check for voltage on the two connections that go into the motor on each setting. If you have voltage on each setting of the switch (except off of course!!) then it's the motor bearings/brushes that are shafted, if you don't then check for voltage on the multi-plug, from there you can find your problem.... ;)

[Critical_Mass 10]

critical_mass in that case, you've either got a broken wire/switch, a broken resistor pack, or a dodgy fan motor that has shafted bearings meaning that the lower voltage that speed 1 gives to the motor isn't enough for the motor to overcome the friction of its bearings... Take the resistor pack off the motor, reconnect it to the wiring and check for voltage on the two connections that go into the motor on each setting. If you have voltage on each setting of the switch (except off of course!!) then it's the motor bearings/brushes that are shafted, if you don't then check for voltage on the multi-plug, from there you can find your problem.... ;)

 

cheers henny. now that you mention it the motor did used to squeal esp k cold mornings.

[Henny 0]

yeah, you'll find that if you keep using it on the other lower speeds (ie, not 4), then it'll blow the thermal fuse at some point soon, as the motor will be pulling more current than normal due to the dodgy bearings causing the resistor pack to get hot and pop the thermal fuse.... Fix the motor now, or fix it AND the thermal fuse at some point soon... ;)

[Critical_Mass 10]

Ill bear that in mind cheers. Though jsut noticed that on speed one i cant hear the motor even tryin to work.. would this indicate it more being the metal contacts on the back of the controls?

[Henny 0]

without checking for voltage/buzzing the switch with a multi-meter, you couldn't tell...

[Mawrick 0]

I'v got problems on position 1 - does the heater control panel need to come out to troubleshoot this ?.

 

Also could it have anything to do with the "brass" part on the front side of the control ?.

 

I presume the thermal fuse sits on the blower motor or ?

 

Anyone got any pics of it - and maybe how to troubleshoot the Position 1 error ?

[Henny 0]

if it's just position 1 that's not working, take the multi-plug off the blower motor and check for voltage on the wires in the multi-plug when the switch is at position 1.... If there isn't 12V on any of the wires then it's either a broken wire (unlikely) or a dodgy switch.

 

If there is 12V, and it works on 2,3 and 4, then your fan motor's bearings/brushes are giving up and causing too much friction for the low voltage the motor receives from the resistor pack to overcome... time for a new fan and motor...

 

If it doesn't work on 1,2 or 3, but 4 is fine, then the thermal fuse has gone. (which is internal to the fan on the plate that has the multi-plug connector on it)

 

If any other combination of 1,2,3 or 4 won't work, then it's probably the switch (or possibly, but unlikely, dodgy wires)

 

If any one setting (other than 1) doesn't work, but others do, then it's probably the switch (or, again, possibly dodgy wires)

 

Think that just about covers all possible scenarios... :)

[Mawrick 0]

I'v just tested it, and to me it seem like there is something wrong with the "lip" that slides up on the copper strip - is there any way to replace only this "lip" - as when I short it in the right position it seem to be working fine.

[Henny 0]

sorry, can't help there, I've only ever owned early interior Corrados, so I have no idea about the later heater controls other than how they electrically work.... Sorry....

 

Anyone else? :)

[G60 CS 0]

mine only works on 3 out of the 4 speeds was told it was to do with the fan motor type

[Henny 0]

which 3 speeds, G60 CS?

 

The fans and motors are the same as MKII Golf, it's just the resistor pack (and switch and wiring, obviously!) that's different to give the extra 4th speed...