firebrick

Had such success with my last question being answered, I have another.

The 'wheel' that adjusts the brightness of dash lights on the left side of
dash under the air vent, get real hot.

I noticed this a few weeks ago, forgot about it, but noticed it again last
night.
I mean it's hot enough to make me take my finger off...

**if in any position except full brightness!**
if I adjust the 'pot' for dim dash lights, the area is hotter.

Way back they called voltage adjustment devices rheostats, than we changed
that to potentiometers (pots).
Not sure the proper term used today.

But...this make sense as at low or medium brightness, the pot is a larger
resistance, which means to me it's dissipating more heat. Full brightness,
no resistance.

Is this the way it works?
Should I be concerned?

--


-----------------------------------------------------
When there's a will, I want to be in it.
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Bill H. in Chicagoland
webcams at http://76.16.160.118:8080
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scottm

Concerned? Only if you are concerned that your truck might burn to the
ground.

I would start by making sure it has the correct fuse in it for the inst
lights(not higher amp)(to make sure it isn't a short), then check the dimmer
for bad connections, then replace it.

I can tell you from experiance, once that plastic starts burning it is VERY
hard to put out, and it goes up quick.

meat plow

What year S10?

william r. walsh

Hi!


Well...they *do* get hot in operation. But I've never used one that was hot
to the touch in any user accessible area. Even the one on my '03 S-10 says
"CAUTION: HOT" on the heatsink that is made into the control assembly. The
rubber wheel on it has never been even warm to the touch.


Yes. Either the control is bad (most likely), dirty (not sure how you'd get
it apart nonviolently), or there is something pulling excessive current
(although I'd expect that to blow a fuse at full brightness). You need to
pay attention to this, or a fire could be the result.

William

jon

Someone is trying to tell you that you are not the brightest bulb! Just
kidding.

Yep remove that rheostat and replace. I think you have a frayed wire or
electric is jumping across the back of the switch to other terminals and
grounding out behind the switch.

Do all the bulbs light up, if you have a burned out bulb it could be
shorting out the switch and cause this problem. Remember the lighting
circuitry in the dash is mostly a printed circuit on plastic.

Check the wires with a voltmeter to determine which is hot and which are not
now adjust the wheel and see what is happening when you adjust the wheel,
most likely it is drawing across the terminals to a ground wire on the
switch.

Rebus
"William R. Walsh" <newsgroups1@idontwantjunqueemail.walshcomptech.co m>

jmagerl

Replace not only the dimmer but also the mating connector. Chances are the
heat is being generated in the voltage drop across the connector. Both
halves should be replaced (at least it was that way in my 96) ( Everything
was a nice brown color from the heat)

firebrick

It's a 99

And for all the others that offered advice or asked questions.
Fuse is original value
All dash lights work normally.

One anomaly...which may or may not be connected.

At high highway speeds, I will see a momentary flicker.
In both in cab/dash lights and headlights.
It's so fast, that the first few times I saw it...I wasn't sure it happened.

I took the '99 s-10 to a dealer who tested the alternator and related
components and found nothing wrong.

eugene

Potentiometers are not a new name for a rheostat, a rheostat simply has two
wires, one at one end of the resistor and one on the wiper, a potentiometer
is the same with another terminal at the other end of the resistor element
inside it.
I remember when I opened the switch/knob box on my s10 there was a big
heatsink on it to dissipate the heat, maybe yours came off.