Originally Posted by projectRDM

There's a million different ways to do it, all of which will depend on how you want to. Gauges are very small current drawing devices, you can string them together off virtually any circuit rated at 15A or more. The 'correct' way IMO would be to pull power right off the key switch, it's rated at 30A, then either T all the power wires together or run a loop in/out to each one. There's really no difference. Mine are powered off the switch only because I didn't want them to come with the radio on the accessory circuit but plenty of people use the radio wiring, it's convenient and easy to access, you also have lighting circuits there too so you can do all the connections in one spot.

Originally Posted by BoostedCoupe

You dont need fuses i wouldnt think. Just use a 15a current like russ said and tie all
the gauges into it. My question is, where are all of you guys running yalls wire at. Like the wire for the temp sensor. From the sensor to the gauge. DO yall run the wire therw the whole in the firewall where the enging harness goes?

Originally Posted by BoostedCoupe

You dont need fuses i wouldnt think. Just use a 15a current like russ said and tie all
the gauges into it. My question is, where are all of you guys running yalls wire at. Like the wire for the temp sensor. From the sensor to the gauge. DO yall run the wire therw the whole in the firewall where the enging harness goes?

Originally Posted by projectRDM

You can fuse the circuit for protection, just to keep the gauges from getting damaged, but you'd need to figure a current draw per unit then multiply by number of gauges to get an accurate measure. I'd say not to worry about it.

For the senders, I drill another hole in the firewall and run anything aftermarket through it, that way you can remove the engine and/or harness independently without having to thread other harnesses through them or around. While it looks cleaner to have it all tucked in the engine harness, having to unwrap and pull it all apart is more time consuming. I usually drill below the evaporator drain tube so that anything coming out of the firewall is low and hidden from view anyway.

Originally Posted by DALAZ_68

can u draw me a diagram of what u mean tying them all together


of drill and get rubber grommets from autzone

Originally Posted by projectRDM

Drilling through the firewall always means using grommets. I didn't think that was noteworthy to mention but good point, stupid people frequent this board too.

Originally Posted by projectRDM

As far as a diagram, think about it. You have say six items that all need a signal from one point. So take all six leads, connect all six together at said common point. You can also just do a 'daisy chain' where you string them together like Christmas tree lights, it really doesn't matter. I prefer to tie it all in at one point so all the original wiring for the gauges or whatever I'm installing isn't cut overly short, if need be it can be moved or installed elsewhere without having to add more wire. On my own car I bought molex plugs and made a separate subharness for the gauges, allowing them to be removed without unplugging each unit individually.

Seriously, it's your car, you have the ability to do it how you would prefer it to look/function. There is no right way to do it as long as the connections are secure, free from potential damage, and nicely installed for a clean look. There's tons of good wiring guides all over the internet if you just want to look at harness builds, solder joints, tie wrap installs, etc.

Originally Posted by DrtyRat

Type molex plugs into google and you get = Modular Plugs - Jacks

Originally Posted by DALAZ_68

so how would i go by making the gauges turn on when the key is switched on?

im guessing looping somthing ot the IGN wire

would it be easier to hook straight to the battery and just connecting a toggle switch?

Originally Posted by 40daws

More info on those Molex plugs please.

Originally Posted by DrtyRat

Type molex plugs into google and you get = Modular Plugs - Jacks

Originally Posted by DALAZ_68

which one thoough

any pics of ur set up would help ProjectRDM

Originally Posted by projectRDM

Good Lord, have you paid attention at all? Go get one of your gauges and read the instructions first. That will help you get sorted. Most units have both a constant power input as well as ignition, why on Earth would you run it through a toggle switch to turn them on? You have switched wires throughout the dash, the radio, HVAC, defogger, ignition switch, power window circuit, etc. Decide what circuit you want to tie into, accessory or ignition, pick your source, and connect. If you want to them to come on with the accessory circuit, hit the blue wire behind the radio, if ignition you can use the black/red at the key switch or whatever color it is behind the defogger switch. There should be no part of this run through any kind of jank ass toggle switch. That's disgusting.





Actually I use the plugs at Radio Shack. They're offered in numerous configurations from 2pin up to 12pin and run about $1-3 each. I'm not going to bother finding a link but you guys should be able to understand what a molex plug is, it's the same type of plug throughout the entire car, a male and female end. They're sold with crimp on terminals that snap into the plugs, you can also solder them on.



There are no pictures of anything on my car or my car online, period. That's how shit gets stolen. Plus although I see there's a ton of confusion here it's not enough to warrant taking my own car apart to take pictures. If you can understand the concept of a molex plug, a subharness, and how they're used to interconnect equipment into a car, you're fine. It's as simple as a new radio installed in your car, there's a subharness that plugs it into your existing harness. Same with an S13 gauge cluster, or S13 headlights, a harness that's made to plug into another harness, hence the term subharness.