4WD INDICATOR LIGHT

[echo7bravo]

I have the switch. But the wires are clipped. @Boone83K10 actually posted the switch on a different message board. But that isn't the issue. I need to know how I can wire it up in my new cab. Where each wire needs to go.

 

[echo7bravo]

Pull the knob and rubber boot off of the transfer case range selector shaft. There should be a pair of wires as indicated.

Since the original T/C was an NP 208 there should also be a pair of wires connected to a lamp holder (208's have an illuminated range select display) - you can snip and insulate them because the 205 display doesn't take a lamp.

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If the wires have been cut - or the connector is different (the 208 has a different switch connector so it probably will be), here is the correct pigtail for a 205. Only $22!


http://www.quad4x4.com/cgi-bin/commerce.cgi?preadd=acton&key=90002


FYG - wiring diagram for the 205 4WD indication;

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The socket/lamp for the dash 4WD indication are not part of the PC board. The wires are run as a separate group and the socket/lamp assembly just twists out of the back of the panel. Usually in the far left bay, next to the choke light.

You might not have to change the bulb though. Considering how infrequently that lamp is illuminated, it's a good bet that it isn't burnt out.

BTW - consider yourself lucky that you have the switch that mounts on the T/C. As Mr. bucket advises, they are obsolete and are not easily found. Quad4X4 does sell them, but @ $122 - I'd check the junkyards first.

Found this from one of Jerry's posts. Makes more sense now.

 

[rpcraft]

Not sure if you ever got an answer but there is an independent wiring circuit that runs first to the transfer case and then it runs up to the dash indicator from there. It doesn't connect through the pinned harness on the gauge cluster. If you wanted to you could pull off any switched power source and run it to the switch and then up to the dash in whatever manner you wish.

 

[echo7bravo]

I'm going to crawl under the dash of the original cab in the morning and take a look. I think the harness had been removed by PO in the past. I think I am going to have to fabricate a new one.

 

[hatzie]

The answer is in the 1986 wiring diagrams... The below snapshots are from the left hand side of PDF page 15.
GM switched the ground so they didn't use the traces on the printed circuit.
If the transfer case switch doesn't have a short to ground in the open or closed positions you should be able to switch the hot side and insert a printed circuit terminal in position 14. You may want to try it before you pull the wire all the way to the floor hole to be sure there aren't other bulbs that will be activated by doing this.

If you want to do this the GM way... Salvage parts are the answer.
The 6294974 wedge bulb socket for the 4x4 lamp is obsolete. 12004215 wedge bulb socket for the lever light is only available in bags of forty.
The Pak Con III fuse panel plugs 120046687 and 12004865 are obsolete as well.
The two position Delphi Weatherpak connectors and terminals on the switch and the disconnects in the two lamp sub-harness are easily available from any number of suppliers including Amazon.
If you can find the various connector and lamp shells in a salvage vehicle and use em even if the wiring itself is chopped all to pieces...
You can buy the terminals for all of the above shells and crimp them on your new sub-harness wires with the appropriate crimp tools. The terminals are all still in production and SXL jacketed wire is SXL jacketed wire. Pick your supplier.

The connector and socket part numbers are printed right on the wiring diagram pages in most of this era GM wiring diagrams.

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[echo7bravo]

The answer is in the 1986 wiring diagrams... The below snapshots are from the left hand side of PDF page 15.
GM switched the ground so they didn't use the traces on the printed circuit.
If the transfer case switch doesn't have a short to ground in the open or closed positions you should be able to switch the hot side and insert a printed circuit terminal in position 14. You may want to try it before you pull the wire all the way to the floor hole to be sure there aren't other bulbs that will be activated by doing this.

If you want to do this the GM way... Salvage parts are the answer.
The 6294974 wedge bulb socket for the 4x4 lamp is obsolete. 12004215 wedge bulb socket for the lever light is only available in bags of forty.
The Pak Con III fuse panel plugs 120046687 and 12004865 are obsolete as well.
If you can find the various connector and lamp shells in a salvage vehicle...
You can buy the terminals for all of the above shells and crimp them on your new sub-harness wires with the appropriate crimp tools. The terminals are all still in production and SXL jacketed wire is SXL jacketed wire. Pick your supplier.

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I knew I could count on you.

I think a PO has stripped everything from the transfer case switch back to the wedge bulb socket. the lamp for the shift indicator is there as well the wiring back to the fuse block.

So I think I just need to find or fabricate a wedge bulb socket and rebuild (what was missing in my 86 cab) into my 79 cab

 

[hatzie]

Shouldn't be too difficult. The wedge socket is the sticky wicket but I bet you can find one in a salvage truck.
I'd be tempted to see if the shift lever illumination bulb socket will latch onto the instrument panel. I bet those are easier to find.

 

[echo7bravo]

Shouldn't be too difficult. The wedge socket is the sticky wicket but I bet you can find one in a salvage truck.
I'd be tempted to see if the shift lever illumination bulb socket will latch onto the instrument panel. I bet those are easier to find.

I will figure that part out. Micro-soldering use to be my thing when I was a radio repairman. I just was not sure how the schematics were. Everything I found on the web said pin position 14 of the main harness. I didn't realize there was a completely separate sub-harness.

But I will definitely check out the shift lever illumination bulb socket first.

 

[hatzie]

The old Delphi 12004215 wedge bulb socket for the lever light has been superseded by 12162711. Mouser Stocks this new lamp socket shell.

The wedge lamp socket terminals are odd critters and they took a minute to find. Mouser stocks em. Delphi GM 12089661, 12089134, & 12089139

 

[echo7bravo]

I swapped my old rusty cab for an even older not rusty cab. I got the frame cleaned and painted and the cab bolted in place. So I am going to spend the next few days wiring everything back up and getting my fenders on. Hoping that by the weekend I will be ready to bolt my bed down and start on the interior install.

I usually jump around all over the place working on different things as weather dictates or paint or glue dries on something. But now I am to the point of starting to put things back together and figured while I am wiring things up, I might as well make everything work not just what's needed to work.

 

[rpcraft]

I swapped my old rusty cab for an even older not rusty cab. I got the frame cleaned and painted and the cab bolted in place. So I am going to spend the next few days wiring everything back up and getting my fenders on. Hoping that by the weekend I will be ready to bolt my bed down and start on the interior install.

I usually jump around all over the place working on different things as weather dictates or paint or glue dries on something. But now I am to the point of starting to put things back together and figured while I am wiring things up, I might as well make everything work not just what's needed to work.

I'm in the process of replacing my harness. I got one of those hotrod 21 circuit jobs but I am wondering if it might not be worth it to look into one of the factory replacement ones. Sure its about 1K when it is all said and done but it will leave a lot less to the DIY aspect of wiring.

Then again maybe this is the time to become an expert on how my truck is wired, and possibly simplify it. With the LS swap it does make it easy to chop out all the old controllers for the spark, cruise, etc etc....