I have an ej25 alternator wiring question that you may be able to help with. Essentially my alternator warning lamp is not receiving ground from pin one in the 3 pin connector shown here:
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Wiring in my car is here:
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I can make the alternator warning lamp turn on when I touch the wire going to pin 1 (L) to ground. My pin 2 (S) is receiving 13 volts (going to B+).
Try as I can it seems that pin 1 is open. However if 12 volts is not on it when started the alternator only puts out 13 volts. When 12 volts is on it (from the alternator warning lamp wire) then fields excite and it bumps to 15 volts.
Any ideas? I'm beginning to think it's an internal issue - not much else that it can be! Alternator seems to work fine otherwise...