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2a fuse for instruments

DC_Gearhead

Sr. Member
Joined
Dec 28, 2015
Messages
563
Seems like an obvious answer but figured I’d toss it out there anyway. The 2a fuse in the panel that supplies the instrument panel should have 12v when key is on, right? No key position puts 12v to it.

By the way no gauges work and I just started working on getting the gremlins out of my electrical system tonight. First stop fuse panel...


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B RON CO

Contributor
Bronco Guru
Joined
Jun 29, 2016
Messages
2,412
Loc.
Statesville, NC
Hi, you are correct. The fuse box has an input side from the battery and one fuse clip should have 12v wether the fuse is good or bad.
If the fuse is good, both fuse clips should be hot when the key is on.
Good luck
 
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OP
DC_Gearhead

DC_Gearhead

Sr. Member
Joined
Dec 28, 2015
Messages
563
Hi, you are correct. The fuse box has an input side from the battery and one fuse clip should have 12v wether the fuse is good or bad.

If the fuse is good, both fuse clips should be hot when the key is on.

Good luck



Crap. Was praying it was some weird old school grounding technique. Reverse polarity or something. LOL

Wires coming out both sides on the back of that 2a are light blue with red stripe. I’m not seeing that combo on the diagrams I have for a 68. Trying to track it down without taking old tape looms off.


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Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,835
The fuse is a little funny.

Normally power goes through the fuse first, then the switch, then the load.
But the dash lights are different. Power comes from the switch, then the dimmer (on the switch), then to the fuse in the panel, and finally to the lights
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
47,353
Yes, what he said. That's not power for the instruments themselves. Only for the dash illumination.
So power is only going to be there when the headlight switch is pulled out at least one notch and the rheostat is not turned off.

Paul
 
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DC_Gearhead

DC_Gearhead

Sr. Member
Joined
Dec 28, 2015
Messages
563
Yes, what he said. That's not power for the instruments themselves. Only for the dash illumination.
So power is only going to be there when the headlight switch is pulled out at least one notch and the rheostat is not turned off.

Paul


The fuse is a little funny.

Normally power goes through the fuse first, then the switch, then the load.
But the dash lights are different. Power comes from the switch, then the dimmer (on the switch), then to the fuse in the panel, and finally to the lights



I found my issue. One of my fuse clips was loose and corroded. No connection. Dummy me, just breezes through checking both sides of the fuses. I had power, but the output side of my bottom fuse was not connected to the fuse. Make sense? Either way I made a rookie mistake.

I ordered new replacement fuse clips for all the fuses. Looks like it’s going to be a PITA to solder them in but they were all pretty corroded. My wiring all looks good, so a refurb fuse box shouldn’t kill me.



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