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Ej to Ea Alternator wiring


Naked Buell
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Hey all. I am trying to splice in the wiring from my 88 Rx to a 93 Ej 2.2 and the wiring diagrams I have aren't jiving.

On the Ea I have: 1 big white wire, black/white stripe, & white/red stripe

On the Ej I have: 1 big white wire, black/white stripe, & yellow

 

Obviously, big whites go together, I know the white/red stripe is the charge light on the Ea. 

Which one from the Ej is the charge light?

Or, does someone know another way to figure this out??????

Please advise.

Thx

Edited by Naked Buell
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B/W is for the light. This must be connected for the alternator to charge. It can be fooled with a resistor with similar resistance as the bulb to 12v.

Yellow is for the voltage reference. Wherever you connect this to, the alternator will target 14.5v at. In the OE config, it's tapped into an ignition switched engine fuse in the cabin. That's how it should be done. That said, the results would be acceptable to tap it into a switched power wire just about anywhere, but it might not be as effective at compensating for voltage drop, and therefore might not charge the battery as effectively.

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On 12/26/2024 at 1:46 PM, Numbchux said:

B/W is for the light. This must be connected for the alternator to charge. It can be fooled with a resistor with similar resistance as the bulb to 12v.

Yellow is for the voltage reference. Wherever you connect this to, the alternator will target 14.5v at. In the OE config, it's tapped into an ignition switched engine fuse in the cabin. That's how it should be done. That said, the results would be acceptable to tap it into a switched power wire just about anywhere, but it might not be as effective at compensating for voltage drop, and therefore might not charge the battery as effectively.

Does that mean yellow (EJ) can be attached to Black/White stripe (EA) since that's the remaining unused EA wire?

So the complete wiring would be:
B/W (EJ) goes to White/Red (EA)
White goes to White
Yellow (EJ) ignition switched engine fuse in the cabin

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16 hours ago, idosubaru said:

Does that mean yellow (EJ) can be attached to Black/White stripe (EA) since that's the remaining unused EA wire?

So the complete wiring would be:
B/W (EJ) goes to White/Red (EA)
White goes to White
Yellow (EJ) ignition switched engine fuse in the cabin

I'm really not sure what color, or how it was wired on the EA82. When I made swap harnesses from 90-94 Legacy donors, I would run a separate wire back to the ECU and tie it in to the small circuit that comes straight from the ignition switch (fuel pump relay, ECU, and ignition coil? I think?).

And I definitely don't remember how I did the FrankenWagon.....definitely not "correctly". But it worked, mostly.

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