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88-93 HVAC control panel

3500GMC

What T F, over
Messages
5,543
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Location
Nashport, Ohio
Few questions for the style I have in pic below.. (or was it 88-94 maybe..)

The buttons, are they supposed to be lit up, lights on? The lettering and symbols? Mine aren't.. :dunno:

And the fluorescent display, is there a way to dim this thing when the lights are OFF? It's annoyingly bright when no other lights are on engine running or key on..

Oct28_0001.jpg
 
Yes, buttons are suppose to be lit up. They go out. From what I see are a pain to change out. I have not done it yet and have a few out.

There is no way to dim without the parking lights/head lights on.

They are used from 88 - 94. :thumbsup:
 
SOME of mine light up. What about the headlight switch? Is it supposed to light up also?

How do you get in to replace the lighting?

Don
 
SOME of mine light up. What about the headlight switch? Is it supposed to light up also?

How do you get in to replace the lighting?

Don

These are good questions..

I can say my HL switch does not light up nor do I know if it's supposed to NOR do I know how to get the HVAC panel peeled apart. :D

Guess I will be a learnin'!
 
There are actually 4 different panels available for these trucks.

88 - black color, 3 speed no recirculate
89-90 - grey color, 3 speed no recirculate
91-93 - grey color, 3 speed w/ recirculate
94 - grey color, 4 speed w/ recirculate

To replace the bulbs, you have to get it out of the dash, and split the case (there are 2 screws and a clip) then remove a few small bolts (they are very small, like 4mm) and you can replace the tiny bulbs.

Also, Headlight switch doesn't light up 88-94.
 
Will do. I'd like to figure out a way to dim the display.

Will have to decide now if the new dash goes in as part of the repair- bought a beautiful dark blue 'burb dash at the parts yard there a while back. My current dash is busted up around the defrost vent.
 
There are actually 4 different panels available for these trucks.

88 - black color, 3 speed no recirculate
89-90 - grey color, 3 speed no recirculate
91-93 - grey color, 3 speed w/ recirculate
94 - grey color, 4 speed w/ recirculate

To replace the bulbs, you have to get it out of the dash, and split the case (there are 2 screws and a clip) then remove a few small bolts (they are very small, like 4mm) and you can replace the tiny bulbs.

Also, Headlight switch doesn't light up 88-94.

This helps a bunch. we/I appreciate that.

Now... this 4 speed fan talk... Hmmm... :scratchchin:
 
There are actually 4 different panels available for these trucks.

88 - black color, 3 speed no recirculate
89-90 - grey color, 3 speed no recirculate
91-93 - grey color, 3 speed w/ recirculate
94 - grey color, 4 speed w/ recirculate

To replace the bulbs, you have to get it out of the dash, and split the case (there are 2 screws and a clip) then remove a few small bolts (they are very small, like 4mm) and you can replace the tiny bulbs.

Also, Headlight switch doesn't light up 88-94.

I also appreciate this info. Thank you!!

Is it possible to put a brighter light in there? The lights that do work are very faint and I have to spend more time making sure I touch the correct switch, taking my eyes off the road longer than I like.

The fact that the headlight switch doesn't have a light is a bummer. That corner of the dash is very dark. There are times at night when I'd like to briefly shut down headlights to just the park lights and find it a problem. Fumbling around and not knowing for sure which switch you have your hand on is a problem.

Don
 
I also appreciate this info. Thank you!!

Is it possible to put a brighter light in there? The lights that do work are very faint and I have to spend more time making sure I touch the correct switch, taking my eyes off the road longer than I like.

The fact that the headlight switch doesn't have a light is a bummer. That corner of the dash is very dark. There are times at night when I'd like to briefly shut down headlights to just the park lights and find it a problem. Fumbling around and not knowing for sure which switch you have your hand on is a problem.

Don

Brighter bulbs could be had I bet. I 'think' the HVAC panel gets its power through the dimmer dial like the rest of the ins. cluster.

I'm not a fan of the non-lit rocker HL switch either.. Might see what I can substitute as my switch is a little worse for wear..
 
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