meirman wrote:
In alt.home.repair on Sat, 21 May 2005 22:37:09 GMT "Joseph Meehan"
posted:
meirman wrote:
This is about about my car heater fan. It's not really about home
or electronics repair, but I think you will be able to help me, and
I'd appreciate it.
Can I regrease my electric switch? And if so, what should I use to
remove the old grease? And more importantly, what sort of grease
should I then use to regrease this 12 volt switch?
I have white grease, lithium grease, ball joint etc. grease (in a
grease gun), some wheel bearing grease, "bicycle" grease in a tube
by Schwinn, and maybe one more kind. I even have Crisco. 
Or I
can buy something new.
Thanks for replying.
My '95 Chrysler heater/AC fan speed switch no longer works in
position 2,
That is the answer to your question. It is not the switch that
is bad, it is a resistor that is gone. They tend to fail one at a
time.
Thats what I thought at first, but
a) The switch tested bad in the second position only.
That would be the case if the resistors were integrated in the switch.
b) A friend gave me a control panel from a Chrysler Caravan truck that
he was scrapping**. The second fan speed, all the fan speeds work
fine with his control panel. (I can't just take the fan speed switch
from it because it won't fit in my heater control panel. And I can't
use his control panel because almost all the connections are different
in his control panel. The vacuum hoses are longer, not a problem;
the electrical connection might be in the same place; but the hot/cold
door control cable connects at the left rear corner instead of right
rear, and is meant to come in at a 90 degree different angle. I
tried to find some slack in the cable, but there isn't. (It's very
hard, almost too short, even to connect the cable to the control panel
it was designed for.)
The speed is controlled by the resistors, but if the switch is bad,
then no current will reach the intended place on the resistor pack.
Have you established that there is a separate resistor pack? (It is
often located in the cool air stream to help cool them)
Assuming it is the switch, I would suggest replacing it rather then
trying to fix it. I have never need a car switch that was going to be easy
to fix.
Be sure to use a the special grease made to electrical contacts if you
decide that is needed.
**Same year and same appearance on the front of the control (except
my dim white letters and lines were bright white on his.) but behind
the face plate, a different style of control panel. Everything
rearranged.
On some cars the resistors are built into the switch and in
others there is a separate resistor pack. You need to replace what
ever has the resistors in it. I don't recommend trying to replace
the resistor, just buy the pack or switch.
Note: Often this happens when the blower fan motor is starting to
wear out. If it were mine and unless it is easy to get to that
resistor pack, I
Actually, the resistor pack is rather hard to get to, but the bigger
trouble was that I loosened the screws for a long time, but neither
came out. Couldn't see the other side. But like I say, it works
with my friend's switch.
would replace the motor and the resistor pack. If you can get to the
resistor pack easily, and you can on some cars, I might try just
that, but I suspect you will find it going out again in a matter of
months.
Meirman
--
Joseph Meehan
Dia duit