Main 12v Key on

Nightstang00

Active Member
Mar 20, 2017
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I’m looking to add a key on 12v fuse box to my 93 fox. I am looking for the best source for a 12v key on wire under the dash. I will run that to a separate fuse box (6) accessories powered with key on. Wideband / shift light / Boost solenoid / small other things that I don’t have plans for yet lol. I know there is a main key on near the ignition, just wanting to get some input here.
 
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90sickfox

Wasn't a pretty sight...and I've got big hands
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Mar 2, 2015
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There is a empty spot in the factory fuse box that is switch power. Would have to check with test light. I'd use that appt to power an 80amp 12v relay that would pull power from the battery to power the fuse box. That takes the load off the ignition switch that's known for overheating. The sum of your accessories sounds to be way under 80 amps. A 80amp MAXI fuse and holder should be used at the battery.

You are planning to run sensors off this source so I don't know if the relay will cause noise in the circuit. I wouldn't think so but maybe one of electrical gurus can chime in.
 

Nightstang00

Active Member
Mar 20, 2017
133
12
28
36
There is a empty spot in the factory fuse box that is switch power. Would have to check with test light. I'd use that appt to power an 80amp 12v relay that would pull power from the battery to power the fuse box. That takes the load off the ignition switch that's known for overheating. The sum of your accessories sounds to be way under 80 amps. A 80amp MAXI fuse and holder should be used at the battery.

You are planning to run sensors off this source so I don't know if the relay will cause noise in the circuit. I wouldn't think so but maybe one of electrical gurus can chime in.
I decided to do what you suggested but I used a 35amp relay and used the black / blue wire off the ignition switch. It was 12v switch. Do you feel that this method would be too much for the ignition switch? If need be I can look around the fuse box but I already did it this way lol. I haven’t hooked anything up to the added fuse box yet. I just tested for voltage at the first fused slot in the new fuse box.
 
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90sickfox

Wasn't a pretty sight...and I've got big hands
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Mar 2, 2015
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That will be fine. The relay should trigger with less than 1amp pulled from the switch.
 
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