Courtesy light switches (door jamb/dome light switches)

[dyeager535]

Finally decided I want my dome lights to function with the doors again.

I recall years past when these trucks were everywhere in the yards and I spent a fair time exploring, that I would see different switches for the door jamb. I never really spent the time to figure out what the difference(s) were, but now I probably should.

According to LMC, there were three designs. Parts 11 and 12 here:

http://www.lmctruck.com/icatalog/csb/full.aspx?Page=187
http://www.lmctruck.com/icatalog/csb/full.aspx?Page=187
Does anyone have an idea what the differences are/were? I vaguely recall seeing some with a plastic tip that struck the door. I find it hard to believe that much changed (threads?) since AFAIk the relationship between the door and door jamb there never changed. Maybe the wiring?

 

[obijuank5]

I just changed OEM 1985 metal button switches to the new ones with a plastic head on em. Dimensionally and functionally identical except for the throw of the button. It sticks out further.

 

[rampage]

IDK what the difference is, but when I put on new doors and repainted them I made a 1/2” disk out of thin aluminum and glued it (think I used a soda can and weatherstrip adhesive) to where the metal tip of the switch made contact to the door so it wouldn’t wear the new paint off and create another rust spot.

 

[dyeager535]

I just changed OEM 1985 metal button switches to the new ones with a plastic head on em. Dimensionally and functionally identical except for the throw of the button. It sticks out further.

Is the travel enough so it doesn't dent the door? I notice mine have dents from the head of the switch, and I don't know if that was due to using the wrong switch, or just "normal".

 

[obijuank5]

Button fully depresses on my switches. Did not notice any depression in the sheet metal, not sure I looked well enough though.

 

[nvrenuf]

I've never replaced the switches on my Blazer but every one I've ever seen had a threaded area on the body to adjust it's depth, if the sheet metal is dented then they probably aren't recessed (adjusted) deep enough.

 

[dyeager535]

I've never replaced the switches on my Blazer but every one I've ever seen had a threaded area on the body to adjust it's depth, if the sheet metal is dented then they probably aren't recessed (adjusted) deep enough.

I thought they were just supposed to be threaded all the way in? That's how I had put them in the past...figured all "play" would be adjusted with the length of throw in the switch.

 

[6872xtc]

The metal ones that I have been around would self adjust. They had a sleeve similar to a roll pin which holds the plunger in the main body. When you close the door, it slides the plunger until it hits the sleeve, then both go in together until the door stops pushing. (As long as they aren't seized)

 

[obijuank5]

New one showing no adjustability. Thread in till tight. Otherwise sloppy fit.
They do not injure the door.

 

[6872xtc]

Here is an original in my '90, then one of the new switch before installation.

 

[dyeager535]

New one showing no adjustability. Thread in till tight. Otherwise sloppy fit.
They do not injure the door.

I do like the broad plastic head and seemingly shorter "throw".

This looks pretty similiar/same: https://www.oreillyauto.com/detail/...93389/2478541/1985/chevrolet/k5-blazer?q=jamb

Hmm. According to AC Delco's site, part # 15693389 (what oreillys shows) was used up until 2000 on the trucks. Odd, used on cars supposedly from 1968, only started on the trucks in 1985.

Can be found on Ebay for $8 FYI.

 

[obijuank5]

I got mine from rock auto and an amazing amount of other genuine parts.

 

[dyeager535]

15693389 was indeed the right part number,as shown in post #9. Got the switches in, and while pretty stiff to do, they *are* self adjusting.

The metal tube that appears captured in the nut is not fixed in place. Installed in truck, the switch was way too long, and prevented the door from closing. To prevent damage I pulled it back out and inspected, but it was pretty clear how they are supposed to work. So I put it back in, and just closed the door gently a bit further and further until the door latched. That metal tube is a press fit in the nut, when the plastic "head" of the switch contacts the metal tube, that pushes the tube through the nut. Since the spring on the switch is pretty light, it bottoms out before the tube starts moving.

Of course, the hole on the drivers side was stripped out, I pulled the switch back out, jammed a decent size piece of copper strand in the hole and tightened the switch down. Not ideal (requires solid contact to the body to work the lights, not sure it will hold up to vibration in the long term), but not sure how else you are supposed to fix something like that without welding.

 

[diesel4me]

You could pop rivet a metal plate over the over sized hole and thread it so the switch will screw into it..a 1/8" thick plate should provide enough threads for it...
Another idea I've seen that works is to get a brake line nut fitting for 5/16" tubing and thread the I.D. for 3/8" thread the switch has,and the nut has 1/2" fine thread on the O.D. that you can tap the door jamb hole to,to bush it down to the proper size for the switch..