This might be old news here but if it can help any i post this info

On my 2000 Blazer ZR2 power oprated mirrors only moved the drivers side mirror a little in and the passengers side mirror moved a little out and that was it.
Since both mirrors moved a little i was sure that the problem was in the switch
I took rge switch out of the car and took it apart.
I used elctronic cleaner on the contact points on the circuit board and also used elctronic cleaner on the brass/copper points on the rubber mat that sits under the switches.
The power mirrors was working as new after i did this.

The operating switch panel for the 4WD did only have light on the selected drive sometimes so i did the same on the switch panel with the Auto 4WD, 2WD High, 4WD High and 4WD low.
I took it out f the car and opened the switch panel(keep the switch side pointing down because of 2 small copper parts you see close to the screw driver)and cleaned the circuit board contact points and the brass/copper points on the rubber mat.
When i put the switch panel back in the car all lights came on including a red Neutal light i have not seen before and the switch panel workas it is supposed to.

I also opened up the keyless remote and cleaned the contact points there and the remote works as new

It looks to me like the switches on these cars easily gets dirt and dust in them and that prevent them from working as they are supposed to

 

Ha, interesting, the lights in my 4x4 switch are intermittent, but for the most part just do not work lol. The switch works perfectly fine, just doesn't light up. I'll have to try this, thanks!

 

The keyless remote! I've been having a problem with mine. Changed the battery. No good. I'm ashamed to admit I never thought to clean the contacts. Now it works perfectly! Thanks for the suggestion, Saint.

 

If you take out the switch panel to clean it beware that the rubber contact points on the switches are loose and can fall out if you do not have the side with the switches facing down

 

Sometimes the rubber buttons on the keyless go gets a bit soft after some time so you have to press hard, but you can get a new empty casing and rubber mat with the buttons for $4 and then the remote will be like new

Link to ebay with a new keyless go casings with 4 button pad for $4
keyless remote 1999 Blazer in eBay Motors | eBay

 

This applies to the back glass release button too, I actually created a how-to thread on it a while back

https://blazerforum.com/forum/lighti...-repair-85861/

 

Did the rear glass hatch realese button work with the remote?

I suppose that this goes for all kind of switches for the Blazer

I have only had problem with the switches inside of the car

 

The small copper/brass contacts is for the switch for adjusting the left side mirror or right side mirror and there is nothing that holds them in place in the switch so if you turn the switch upside down they will fall out.

The pictures are from a video somebody posted on youtube that i watched before i opened up the switch for my car

I did not pay attention to the small brass/copper contacts and managed to drop one of the small contacts on the kitchen floor and had a hard time to find it

You can see the 2 small copper contacts inside the red circle in the picture

 

The positive terminal/the clamp that holds the battery in place on the keyless remote breaks loose as it often does and did on my keyless remote it is easy to solder back in place

On the picture below to the left you can see the 3 ponts where the clamp is soldered to the circuit board

On the picture below to the right you can turn the circuit board, lay it on a flat surface and gently press down on the curcuit board so the 2 solder points on the clamp will slip in the 2 small holes in he circuit board so you can solder the 2 points from the side shown in the picture to the right.
It is much more easy to solder the clamp back in placedoing it from this side
The solder points are shown with red arrows on each side of the circuit board except for the middle solder point which i solder from the side as seen in the picture to the left

 

I've done this trick on my Jimmy window switch, and on 2 of a friend's ford window switches:

Pull the switch, and put it in a jar, 1/3 full of VERY soapy water, and shake well. Repeat until no sediment in the jar bottom, the do it again with clean water.

Then do it again with paint thinner (or some thin petroleum fluid (NOT GAS)), to displace the water. Shop-Vac out the excess, and re-install.

First did the Jimmy switch like this about 8 years ago. Been working ever since...