Alternator wiring help needed on 6/72 FJ40 (1 Viewer)

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scoobiedubes

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rewiring most of my 40 and need some help with the alternator to voltage regulator wiring. The voltage regulator wasn't working right so I'm replacing it, and it didn't have any labeling to help me re-wire to the new one (looks like it was some aftermarket brand). My wiring diagram shows that there should be two white/black wires coming from the alternator plug, but I've got one white/black and one white/green wire. Any idea which one of these is the "E" and which is the "F"? Here's some pictures of the plug, as well as the cut wires going into the alternator:

altwiring2.jpg


altwiring3.jpg
 
White Black stripe = E / Earth / Ground
White Green stripe = F / Field

The alternator has an internal ground but thats difficult to read in the diagram , thats why you think you need 2 wires. In the diagram you see this ┴ symbol next to the E terminal wich means in this case internal ground and not a 2nd wire.

BTW; On the VR side should be a third wire (IGN) that goes to the Ignition key fuse.

Good luck,

Rudi
 
Last edited:
Toss that old unit & upgrade to the 2F alternator w/internal regulator. They were 25 bucks on Rock
Auto last time I looked. The field lead is wired to the ignition switch so it has power with the switch on & that is it. Very simple install though it may require some shimming. I used my F mount & bracket & wired the field lead to the power plug for the regulator.
 
White Black stripe = E / Earth / Ground
White Green stripe = F / Field

The alternator has an internal ground but thats difficult to read in the diagram , thats why you think you need 2 wires. In the diagram you see this ┴ symbol next to the E terminal wich means in this case internal ground and not a 2nd wire.

BTW; On the VR side should be a third wire (IGN) that goes to the Ignition key fuse.

Good luck,

Rudi

Thanks! but there are 3 wires still right? E, F, and B? And the regulator has E, F, and ignition? That's what my diagram shows, just double checking.
 
Toss that old unit & upgrade to the 2F alternator w/internal regulator. They were 25 bucks on Rock
Auto last time I looked. The field lead is wired to the ignition switch so it has power with the switch on & that is it. Very simple install though it may require some shimming. I used my F mount & bracket & wired the field lead to the power plug for the regulator.

Hmm good advice, I'll have to check that out. Other than the simpler install, any other advantages?
 
No, not really.

Since you have the new VR, the simplest thing would be to just go ahead and wire it. Like Rudi said, there are only 3 wires necessary. The white/red ignition wire from the engine fuse, the white/green field wire from the VR to the alt and the white/black ground wire.
 
No, not really.

Since you have the new VR, the simplest thing would be to just go ahead and wire it. Like Rudi said, there are only 3 wires necessary. The white/red ignition wire from the engine fuse, the white/green field wire from the VR to the alt and the white/black ground wire.

Awesome, thanks guys! Should be a piece of cake then, just needed to know which wire was which. I'm sure I'll have more questions as this rewire goes along. I've got lots of bookmarks to different threads already, but my wiring diagram failed me in this case. My rig has had almost nothing electrical that works other than the headlights, so hopefully I can get the rest of it workin soon! Trying to take it one small chunk at a time.
 

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