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Old 03-29-2010, 12:43 PM   #1
Scootin 81 C20
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Tach Wiring Help.

Hey guys, I was going through a box in the garage and I found a tach that I want to hook up in my truck to keep an eye on things. I know where the two wires for the light go to, one blue wire(-) and one yellow wire(+), but the wires for the tach itself have me confused. The two wires for the tach are one green wire and one black wire. I'm pretty sure that the green wire goes to my tach output on the distributor, but where does the black wire go to? Any help is appreciated.

Thanks
Benjamin.
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Old 03-29-2010, 01:44 PM   #2
JW76
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Re: Tach Wiring Help.

i think the black is just a ground

if i recall correctly my tach had 4 wires red white green and black

red was to the fuse box for ignition power
black was ground
white was illumination which i put into the illumination slot in the fuse box
green was signal
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Old 03-29-2010, 02:59 PM   #3
Scootin 81 C20
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Re: Tach Wiring Help.

If it helps any, the brand of tach is Hawk.
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Old 03-29-2010, 05:42 PM   #4
BigRed76
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Re: Tach Wiring Help.

Green should go to the distributor, and on every tach i've ever seen the black is ground.
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Old 03-29-2010, 06:11 PM   #5
Hoods69BadBowTie
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Re: Tach Wiring Help.

Quote:
Originally Posted by JW76 View Post
i think the black is just a ground

if i recall correctly my tach had 4 wires red white green and black

red was to the fuse box for ignition power
black was ground
white was illumination which i put into the illumination slot in the fuse box
green was signal
Yep that sounds right if I remember correctly! I put my white to my headlights so it only comes on when the lights are on!
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Old 03-29-2010, 06:21 PM   #6
JW76
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Re: Tach Wiring Help.

if you tap the white into the fuse box where it says illum... like you said it turns on with all the interior lights and you can dim it also
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Old 03-29-2010, 06:56 PM   #7
Benelli
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Re: Tach Wiring Help.

Green goes to dist.
Black is ground

I'd put it with headlights, like stated, so it lights up at night but stays sun-lighten at day.
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Old 03-29-2010, 09:11 PM   #8
Scootin 81 C20
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Re: Tach Wiring Help.

Well guys, I wired it up and it worked fine at first, but after about two minutes it started saying that my truck was idling at 4,500 rpm. on the V8 setting. That's not right, so I think the reason I ended up with the tach is that it is burnt up. I need to find a different one I guess.
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