Fan switch troubles?

[cory]

1991 Diesel Jetta:

So the other day I went to turn on my interior fan to find that suddenly, it only works on high.
I took the switch apart, the contacts were a bit fouled, cleaned them, tried again...same problem. Cleaned more...same problem.

Anyone have experience/knowledge with the fan switch/blower and could offer me some insight as to what the issue may be?

Thanks
Cory

[madrogers]

probably the fan reostat (speed control coils) located behind the glovebox in the heater air ducting after the fan but before the heater box , if the coil burn out you only get high speed  , the power does not go thought the coils

[cory]

Sweet !!! That sounds like good info.
I'll check b4 I loose light for the day.

Thanks

[Quantum TD]

There's a trick in the vortex MK2 DIY section about using a fuse or resistor from radio-shack and fixing it for like $2.

[Baron VonZeppelin]

Let us know how it plays out on the 89.

The 89 i'm fixing to start working on has the same symptom (only high speed works). Hoping its in the dash fan control switch - but not touched it yet.

Interested in what you learn.

The other 89 that i drive daily was doing opposite - everything but high speed worked. It was a connection on the dash fan speed switch.

Free fixes are so rewarding. 

[cory]

I will let you know what I find for sure. I started getting into it this evening but need a little more info and time.

Do I need to pull the ducting apart to get to that rheostat? That is what I have started doing...what a painus in the anus. I am now holding out a little hope that the rheostat is attached to the blower.?.

I like the idea of the $2 fix. Not quite to that point yet as I have never heard of a rheostat let alone seen one. So hopefully I can get to it and try the cheap fix.

Thanks for all the input thus far.

[cory]

Hey Quantum TD,

Would you mind posting a link that DIY section. I poked around a bit but no luck finding it.

Thx

[madrogers]

my 91 diesel w/air has the reostat just left of the blower moter assemble up on the diaginal part of the duct it is screwed in with about 4 wires going to it and is white plastic  I do not remember what i had to do to get to it i was just wreaking the car .
Mark.

[Quantum TD]

Here you go:

http://forums.vwvortex.com/zerothread?id=2665283

[cory]

Thx. You da bomb.  hehe

[Smokey Eddy]

THANK YOUUUUU

[cory]

I think that I have the right piece to repair now. It was actually in the blower housing.
I read through the vortex post and will try this route first.

I would like to lube the blower/fan/motor so that it spins a little more freely and hopefully avoid this happening again.

Can anyone tell me where good spots to put some grease would be?

Thx and more later.

[calituner]

the blower motor isnt servicable. i wouldnt grease it or lube it at all.
the blower motor resistor is what its called not a reostat. reostat is a variable resistor. the blower motor resistor is a three different resistors of different ohms.

[madrogers]

the blower bushing are at each end a drop of oil would soak in to help lub it not grease, I have drilled a small hole in the end between the wire hookups and oiled it there (1/16" hole ) it worked great. sorry for confusion over the reostat / resistor block , I had heated seats on my mind useing a dimmer switch for controlling them.
Mark.

[smutts]

The "made in france" bit written on the side of the blower explains a lot. The bearings dry out, the motor needs to draw more juice to turn itself, the rheostat gets hotter due to extra juice, the fan (that also cools the rheostat) runs slower due to the extra friction and so rheostat gets double whammy hotter. This causes the thermal fuse to blow. Twenty Bob $1.50 to get a new one. Or if you are as tight as a badgers arse solder in a bit of copper wire to bypass, then find out why the thermal fuse was there when your dashboard bursts into flames the next time the bearings dry out.

Oiling is bit of a git, but access to the relevant bearings can be done by drilling 4mm holes in the plastic fan near its hub, bit of sewimg machine oil works.