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General Information => Troubleshooting => Topic started by: cory on September 23, 2009, 05:01:29 pm

Title: Fan switch troubles?
Post by: cory on September 23, 2009, 05:01:29 pm
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
Title: Re: Fan switch troubles?
Post by: madrogers on September 23, 2009, 05:39:44 pm
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
Title: Re: Fan switch troubles?
Post by: cory on September 23, 2009, 06:01:09 pm
Sweet !!! That sounds like good info.
I'll check b4 I loose light for the day.

Thanks
Title: Re: Fan switch troubles?
Post by: Quantum TD on September 23, 2009, 07:37:28 pm
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.
Title: Re: Fan switch troubles?
Post by: Baron VonZeppelin on September 23, 2009, 09:10:35 pm
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.  :)
Title: Re: Fan switch troubles?
Post by: cory on September 23, 2009, 09:34:11 pm
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.
Title: Re: Fan switch troubles?
Post by: cory on September 23, 2009, 09:40:27 pm
Hey Quantum TD,

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

Thx
Title: Re: Fan switch troubles?
Post by: madrogers on September 24, 2009, 06:36:50 am
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.
Title: Re: Fan switch troubles?
Post by: Quantum TD on September 24, 2009, 09:39:10 pm
Here you go:

http://forums.vwvortex.com/zerothread?id=2665283
Title: Re: Fan switch troubles?
Post by: cory on September 24, 2009, 10:03:22 pm
Thx. You da bomb.  hehe
Title: Re: Fan switch troubles?
Post by: Smokey Eddy on September 25, 2009, 03:50:44 am
THANK YOUUUUU ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D
Title: Re: Fan switch troubles?
Post by: cory on September 26, 2009, 11:28:20 am
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.
Title: Re: Fan switch troubles?
Post by: calituner on September 29, 2009, 10:41:53 am
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.
Title: Re: Fan switch troubles?
Post by: madrogers on September 30, 2009, 12:24:47 pm
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.
Title: Re: Fan switch troubles?
Post by: smutts on September 30, 2009, 01:26:14 pm
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.
Title: Re: Fan switch troubles?
Post by: calituner on September 30, 2009, 02:19:58 pm
drilling the hole works well for the outer bearing. but what about the inner bearing near the fan blades? youd have to pull the fan out to oil them. imp saying its not worth it.
Title: Re: Fan switch troubles?
Post by: cory on October 04, 2009, 09:31:55 am
Sorted...just in time for the chill.  ;D

So I tried the soldering in a new thermal fuse but was having trouble with the solder taking. Not wanting to mess with it any longer I just ordered a new resistor plate, installed it, changed a fuse that had blown somewhere along the way, and whammy back to 3 speeds on the old fan.

I did do a little oiling with a cool little precision oiler I found at R. Shack. No holes drilled but with the little oiler I got into some tight spots. I will go back in on a day soon and drill and oil the other spots...can't hurt.

Thanks all for the help.

Enjoy the fall. I just pressed 5 gal of cider yesterday which will turn into hard cider in the next few weeks !!!

Cheers
Cory
Title: Re: Fan switch troubles?
Post by: Quantum TD on October 04, 2009, 08:12:21 pm
Top five things I miss about the north:
1) Real autumns
2) Vegetables and fruits that actually taste like something
3) Fresh seafood
4) The beach
5) Fresh-pressed apple cider.
Title: Re: Fan switch troubles?
Post by: cory on October 04, 2009, 08:18:00 pm
The Beach? Not something I generally equate with the north. Out of curiosity, what beach do you have in mind?
Title: Re: Fan switch troubles?
Post by: jtanguay on October 14, 2009, 10:17:31 am
this makes me want to go to princess auto and buy one of those squirrel cage fans running off A/C power and mount that, and hook it up directly to the 3 phases of the alternator. for those who want to try it, you need to connect 2 of the phases for the one lead, and the other phase for the other. it will definitely work, and find an old fan with a 3 speed switch and hook it up  ;D

some sealed bearings could be used on the squirrel cage fan to make it bullet proof  8)