Where to get power for tach...?

[Green79Scottsdale]

Where are you guys getting the 12v power supply for your tachs? After studying the wiring diagram for my truck, it looks like there is a terminal on the fuse block for it. I looked at the one in my truck and it is in deed open. Can I plug into that to get power? Or is there something more that needs to provide power to that specific spot on the fuse block? Electrical stuff is most definitely NOT an area that I am confident with. Any help would be greatly appreciated. Pictures will get you a round or two of adult beverages if/when we ever meet.

I understand the ground and lead to distributor part of the install, it's just the power supply I don't fully understand.

 

[oneluckypops]

Simple solution would be to connect a testlight to ground, then probe the terminal you are wanting to use, if it lights up then that is a 12v source.

 

[notverrysmart]

Don't have any pics from where I had mine but I just used a spade terminal going to the fuse block for 12v, wouldn't hurt to throw a fuse in there if it doesn't already have one. I would double check first to make sure you have switched (nothing with key off, 12 with key on) 12v before plugging it in.
For the gauge light you can do it 1 of 2 ways, either tap into your lights and it will come on with them or connect to the power wire going to the fuse block.

 

[crazy4offroad]

I connected mine to an ignition switched source, not always hot or it will drain your battery.

 

[Green79Scottsdale]

Simple solution would be to connect a testlight to ground, then probe the terminal you are wanting to use, if it lights up then that is a 12v source.

Okay. For this simple mind of mine, How is a quick simple way to make a test light? I have nothing like that around here, but I have a feeling it will be handy for many things.

 

[crazy4offroad]

Tail light pigtail, or side marker light pigtail, if you have an extra.

 

[Green79Scottsdale]

Okay, let me explain it this way. I know it needs to be an ignition switched source, hot only with key on. The problem is, I am not smart to the point to know where those sources are. Looking at the wiring schematic I have does not really help me much either. I am confident the fuse box is one such source, correct? Other than that, I really do not know much, I am an electrical idiot.

So far it is going to go like this. Test the fuse block for 12v (notverrysmart) with a test light (oneluckypops) made out of a light pigtail/socket, if I have one laying around. You all are a help by the way, thanks!

Will check back later with results.

 

[notverrysmart]

If you have a volt meter you can use that as well. You could also use some wire a light bulb and electrical tape if you want to go really ghetto lol

 

[crazy4offroad]

If your truck is the 79 in your details you should have a fuse block that's the old style with the glass tubes instead of the newer blade style push-in fuses. Near some of the fuses should be like male spade style connectors recessed in the housing. Turn your key to the "On" position and start testing some of them. Once you find a hot one turn the key off and see if your light turns off. Once you find an ignition source crimp/solder a female spade connector on and just plug it in!

 

[oneluckypops]

Okay. For this simple mind of mine, How is a quick simple way to make a test light? I have nothing like that around here, but I have a feeling it will be handy for many things.

I agree with C4 I would want to use an ignition hot source aswell. Like someone already stated make sure you use some type of Fuse Protection. As for a test light yes you can remedy one out of a light socket, illuminated rocker type switch, ect... Or you could go to the Parts store and pick one up for about 5 bucks. If you plan on doing a lot of electrical work I would splurge for a better tester, Mine is a snapon with a coiled up cord which makes it nice for storing with out getting it tangled up, also the bulb in mine lasts much longer then the elcheapos. But the elcheapos work JUST FINE for the occasional DIY kind of guy.

 

[Green79Scottsdale]

If your truck is the 79 in your details you should have a fuse block that's the old style with the glass tubes instead of the newer blade style push-in fuses. Near some of the fuses should be like male spade style connectors recessed in the housing. Turn your key to the "On" position and start testing some of them. Once you find a hot one turn the key off and see if your light turns off. Once you find an ignition source crimp/solder a female spade connector on and just plug it in!

It works! After I got into it and started messing with **** with the directions you gave me it started to make sense. My neighbor ended up having a neat LED test light. I knew what connection my wiring diagram said they go to from the factory so I started there, and it is a switched power source like I was hoping it would be. I checked some of the other spots in the fuse block to see if they were switched or not for future reference.

C4 thank you for explaining it nicely for me. Yes it is the 79 in my details, but it has one of the "newer" style blocks with the blade fuses, not the glass tube types.

I still feel like I know nothing about wiring. Probably because I just don't mess with it that much.

 

[Green79Scottsdale]

I agree with C4 I would want to use an ignition hot source aswell. Like someone already stated make sure you use some type of Fuse Protection. As for a test light yes you can remedy one out of a light socket, illuminated rocker type switch, ect... Or you could go to the Parts store and pick one up for about 5 bucks. If you plan on doing a lot of electrical work I would splurge for a better tester, Mine is a snapon with a coiled up cord which makes it nice for storing with out getting it tangled up, also the bulb in mine lasts much longer then the elcheapos. But the elcheapos work JUST FINE for the occasional DIY kind of guy.

I am going to look into buying one. I figure one built for the purpose will be better than some crap concoction I come up with.

 

[crazy4offroad]

Glad it worked out! I need to track down a gremlin in my radio wiring. I hit a bump and it goes off and comes back on. I guess when I jumped it at last year's hill & hole race and the radio ended on sitting on my gas pedal foot didn't help matters any..