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Wiring (EZ, 4G, DUI)

kiteoregon

Full Member
Joined
Nov 21, 2011
Messages
292
Has anybody wired up the EZ harness with the 4G alternator and a DUI? Happen to have the wire map / schematic you used?

Thanks.
 

Viperwolf1

Contributor
electron whisperer
Joined
Aug 23, 2007
Messages
24,448
The white (alt exciter) wire goes to the green wire at the alternator plug. The yellow wire at the alt plug goes to constant 12V (you can connect it to the B+ terminal on the alt). Follow the diagram below with regard to the B+ terminal wiring.

http://www.bcbroncos.com/4g alt.pdf

DUI just needs switched 12V (red wire in EZ harness) to the BATT terminal on the DUI.
 
OP
OP
K

kiteoregon

Full Member
Joined
Nov 21, 2011
Messages
292
Do i need to worry about the red wire labeled Alt Power? Some posts indicate that the Red Alternator Power wire should terminate with the yellow and not connect the yellow to B+. I am thinking that if the yellow is terminated at B+ then the red wire is probably not needed?

What about the Alternator bypass wire that comes with the kit? Instructions say it's needed for 80 Amps or more and it needs to be connected Alternator RED battery post to Starter solenoid where the battery cable connects to the starter solenoid. I already have a 4GA wire with a 175a fused link, I don't imagine i need this wire in addition?
 
Last edited:

Viperwolf1

Contributor
electron whisperer
Joined
Aug 23, 2007
Messages
24,448
Do i need to worry about the red wire labeled Alt Power? Some posts indicate that the Red Alternator Power wire should terminate with the yellow and not connect the yellow to B+. I am thinking that if the yellow is terminated at B+ then the red wire is probably not needed?

What about the Alternator bypass wire that comes with the kit? Instructions say it's needed for 80 Amps or more and it needs to be connected Alternator RED battery post to Starter solenoid where the battery cable connects to the starter solenoid. I already have a 4GA wire with a 175a fused link, I don't imagine i need this wire in addition?

You won't use the Alt Pwr wire for it's intended purpose. You will use either the 4 gage you have now or the bypass wire to carry all the charging current, you don't need both. The problem is you need to do something with the red wire so it doesn't short to ground or get fed a bunch of current that it can't handle. Tying it into the yellow wire is a good solution.
 
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kiteoregon

Full Member
Joined
Nov 21, 2011
Messages
292
So i have a 175A mega fuse on the 4GA line between the alternator and the battery. Do i need to fuse any other wires at off the + post on the battery or solenoid?
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
51,616
Yes, normally anyway.
The new wire that powers the fuse box (probably a big Red one?) usually marked as such, will need a fuse or fusible link to protect the main circuit.

The factory used a fusible link, but I like replaceable fuses myself. Never had one blow, but if it did out on the trail, the fix would be much easier with a fuse. Assuming you could find the actual offending short first of course.

I like 60 amp Maxi-Fuses myself. Bigger than most push-in fuses, but not as bulky as the Mega-Fuse we typically use in the charging circuit.

paul
 

ntsqd

heratic car camper
Joined
Jan 30, 2005
Messages
5,953
Loc.
Upper SoKA
Advantage of a fusible link over a fuse is that a fusible will take a short term over-load (think motor in-rush currents & stuff like that) better than all but the somewhat rare "Slo-Blo" fuse.

To address the not so easy to field repair issue with fusible links I came up with this on our CTD:
i-Bp5bTr9-L.jpg


Power comes in on one terminal, the protected circuits go out on others, the fusibles jumper from one to the other, and spare fusibles are stored on the end terminal.
(The 80A breaker is camper's battery charging connector.)
 
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