84 c20 gauge pin out

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seniorbear69

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steve
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1984
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c20
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350
HI can anyone help me .can you tell me the pin out for the gages .i have lge fule temp oil pressure and volts .thanks
 

AuroraGirl

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· Left turn signal is light blue? Yep

· Right turn signal is dark blue? Yep

· Fuel is pink. Im converting to single tank from dual, can I just splice/tie the pink and pink with black wire at the tank selector switch?

Probably just a nomenclature issue, but the fuel tank level indicating circuit does not involve (or even pass through) the tank select
switch. I'm guessing you mean the tank transfer valve.

NOTE: The PNK lead (that connects to the switch on the dash) is the power supply for the transfer valve and is hot from the fuse
block. Do not splice into that.



The pink sensing lead for the gas gauge runs through the firewall at the main connector block and then joins in with the rear lighting
group. It pops out of the rr lighting conduit between the cab and bed. An extension lead (also pink) is spliced on at that point. After
that it runs over to the transfer valve. If you plan on using the RH (auxiliary) tank, then yes, cut the PNK/BLK at the transfer valve
and splice into the PNK. If the LH tank is to be used, just run the PNK straight to that tank. Wiring diagram is attached below.


· Oil pressure is tan? Yep

· Parking brake is tan/white stripe? Yep - actually two TAN/WHT leads (one each from the e-brake and proportioning/combination valve)

· High beams wire is light green? Yep

· Illumination is brown? Yep - but it's actually gray, there is no brown lead into the cluster

· Coolant is dark green? Yep

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found this
 

seniorbear69

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thanks for yore replys but that not whot i ment .i need to know whot the pins on the gages are for .power/ground /sender etc etc
 

75gmck25

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On this site there are PDFs posted that have the wiring diagrams for each year of truck. Just download them and start tracing the wiring.

All wiring for the gauges, except the tachometer, runs through a large multi-pin plug that plugs into the instrument cluster. The optional tach has its own 3-wire plug.

And to repeat the question: What are you trying to do?
 

seniorbear69

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trying to wire the gages into a difrent surounding that has no printed circit .i do not have the original circuit mounting etc just a bunch of gages with pins .whot do thay do .i do not know ! a good photo of the back of a cluster to follow to the multiplug would help
 

AuroraGirl

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trying to wire the gages into a difrent surounding that has no printed circit .i do not have the original circuit mounting etc just a bunch of gages with pins .whot do thay do .i do not know ! a good photo of the back of a cluster to follow to the multiplug would help
would you rather buy another printed circuit and just do that. at least then you could visualize and understand it that way
 

Raider L

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@seniorbear69,

Oh man, I'd like to jump in here but right now I don't have the time to look at my schematic. I could tell you in a second because I've been studying the gauge part of the schematic just for that purpose when I was looking at the Amp. gauge wiring. I'll have to get back to you tomorrow. See, I cut my gang plug off and removed the printed circuit when I put in all Autometer gauges. I had to follow each wire where it went to the gang plug and instead connect the gauge wires to the backs of each one of the gauges seperately for the Autometer gauges. Let me get back to you.

In the meantime you can look up the schematic like @75gmck25 said and start familiarizing yourself with the numbers like "20p/w56". That is a made up number but what you'll find is the wires are all numbered like that. In my example, "20" is the size of the wire, or 20 gauge wire, little bitty. Next is "p/w". That means that the color of the wire is pink with a white stripe down the length of it. Many of the wires in your truck will have a base color but to designate that it might be associated with that wire another branch of where that wire goes will have the same base color of the main wire but it's splice has a white line down the wire along with the base color. Lastly the number "56" means that the wire may go into the fuse block at the firewall down there and it's location is hole number "56". Each hole a wire goes into has a number and on the other side of the firewall where the fuse block is to the left of your brake pedal on the firewall has the same numbered hole where that wire comes out into the cab. That wire will go to a gauge, or the ignition switch, or something like that.

So start looking at that schematic. It'll look like nothing but a confusing ball of string at first but as you start seeing that the wire that comes off the water sending unit on the block has a size, a color, and a location in the fuse block, going to your water temp gauge. That's how you start, begin with something simple.
 

seniorbear69

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RAIDER L that would be great .ihave wiring diagrams that i purchased from classic parts .from them i can follow all the wires from sender to plug .the problem is from thear to the gage its self.the new loom i have dus not have the plug. also i have nothing to plug it into the plastic surround for the gages that held the printed circuit is toast so is the circuit melted and destroid but the gages and facia are good.as aurora said i could order the printed circuit the assembly to hold the gages etc etc .but im in the uk by the time ive purchased them inported them paid duty tax and vat its a hefty sum so i can make an mounting to hold it all wire my new loom direct to the gages screw it all in the truck and no one will know .hence i need to know whot the pins are for piower ground sender so i dont fry em all when i flick the key .thank you all for yore help.steve
 

Raider L

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@seniorbear69,

You need another "box" that the printed circuit lays onto. The plastic "box" has the places for the bulbs, and metal clips for all the gauges to "plug" into. There are pins on the back of the gauges that you push into those metal clips and the clips make contact with the printed circuit. This box also has the holes for all the bulbs. See, the printed circuit carries the power from the "gang plug" that you plug into the back of the box.
That box is either white or a duck egg green in color. If you can order that then you'd have pretty much all you'd need to rebuild your instrument panel. Just make sure whoever or wherever you get it from supplies all the clips for the gauges. Unless you saved all of them from your melted box you had. Then all you need is the box. I'm pretty sure you know all this, and it might not be as much to ship it because it doesn't weigh much at all. Make sure your printed circuit is okay from whatever melted your box. All it takes is one melted track and the circuit wouldn't work, or only part of it would work.
Yeah, shipping even inside the U.S. is getting ridiculous.
 
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