12v power source to tap into?

[jmac57]

i put in new gauges in my 97 camry le but i need to find where the 12v power source is in the car is so i can tap the red wire into it... anybody know where i can find it and what (if any) panels will need to be removed to get there?

[Jimnist]

Deja vu. I posted the exact same thread in the gen 2 sub-forum. Probably easiest to hook it into the 'ACC' wire for the radio/headunit. That one will only gives power when they key is on the ACC or ON. Make suer it's not a constant because it will still power the gauge, even with the key OFF and will drain your battery. Test it with a multimeter beforehand, get one if you don't have one; they're pretty vital tool.

If you have two wires, one for the gauge and one for the night-time illumination(backlight) and wire both to the ACC, the backlight will turn on straight-away when the key is turned. If you want it to only be on when the lights are, you're going to have to find the correct wire to tap into. I suggest try tapping into the dimmer switch for that, but test it before to make sure. That will be easiest as you know where it is; instead of searching through the harness coming off the combination switch(for indicator, lights, wipers e.t.c)

[DxElite]

You can use "

Add-a-Circuit

Add-a-Circuit

" fuse tap type accessory. You won't have to go hunting and tapping wires and you'll get added protection with a fuse for the gauge.

You just remove the radio fuse and plug this thing in, one fuse is for the radios and the other is for your gauge.

I used one of these when I hardwired the power cord for my radar detector.

[jmac57]

Originally Posted by Jimnist

Deja vu. I posted the exact same thread in the gen 2 sub-forum. Probably easiest to hook it into the 'ACC' wire for the radio/headunit. That one will only gives power when they key is on the ACC or ON. Make suer it's not a constant because it will still power the gauge, even with the key OFF and will drain your battery. Test it with a multimeter beforehand, get one if you don't have one; they're pretty vital tool.

If you have two wires, one for the gauge and one for the night-time illumination(backlight) and wire both to the ACC, the backlight will turn on straight-away when the key is turned. If you want it to only be on when the lights are, you're going to have to find the correct wire to tap into. I suggest try tapping into the dimmer switch for that, but test it before to make sure. That will be easiest as you know where it is; instead of searching through the harness coming off the combination switch(for indicator, lights, wipers e.t.c)

hmm how would i know which wire that is? that sounds like what i want to do i just dont know which wire that actually is...



as for the double fuse thing i will go to my local auto store but i dont particularly feel like ordering anything ya know? hurts the cards lol but i think that could be the easiest way to do it...



ill get back to ya guys in a couple days if either work thanks for the response

[Jimnist]

Originally Posted by jmac57

hmm how would i know which wire that is? that sounds like what i want to do i just dont know which wire that actually is...

Test it with a multimeter, get one if you don't have one as it will be an important tool. Can be had from electrical stores and auto shops. There should be instructions, but basically you make sure you set it on the right setting(for something that can take 12v), take the positive probe and put it to the wire your testing and the negative to a good ground(otherwise it won't register even if it does have 12v). Test with ignition at both off and 'ACC' to make sure it switches off with the key off.

If you replaced the headunit, there will most probably be writing on the wires stating what it is i.e. constant 12v, ACC(the one you want), ground and then all the speaker wires.

And yes, this method is 'free', providing you have a soldering iron and solder, but it means you have to cut into the factory harness. I don't really like the idea of it, but did it anyway as i couldn't be stuffed to look around for empty fuses or relays.

[jmac57]

ok so cutting into the stock wires scares me alot so that will definitely be the last thing i do lol

but i picked up one of those fuse things and i still cant get it to work :/ perhaps im just in the wrong fuse?

[DxElite]

Double check you're using the radio fuse socket, that one is 12V for sure.
You could also double check if there is power coming from the wire of the fuse tap thing with a voltmeter.
Also might want to double check the connectivity of your wires, make sure everything is wired right and there's no break in the wires, including the grounding wire.

[Jimnist]

Originally Posted by jmac57

ok so cutting into the stock wires scares me alot so that will definitely be the last thing i do lol

but i picked up one of those fuse things and i still cant get it to work :/ perhaps im just in the wrong fuse?

'Cutting' isn't that bad. You're just stripping the original insulation on the wire and then soldering a wire onto it.

Like DxElite said, check with a multimeter/voltmeter; same thing, different name.