Subaru 110amp alternator swap, now no batt or oxs dash light

[MrTibbs]

So w/ the recent posts on upgrading the subaru alt. w/ a 3.6 one. I ordered an OEM on ebay, however a 2.5 liter one showed up at my door (23700AA63A).

I decided to put it in anyway. I had to add a shim on the pulley to push it out so the AC belt would not rub, but once done mechanically everything was good.

Since upgrading on a 92 2.2 engine, I needed a new 3 wire pigtail (http://www.amazon.com/gp/product/B00AY24NFC/ref=s9_simh_gw_p263_d0_i2?pf_rd_m=ATVPDKIKX0DER&pf_rd_s=desktop-1&pf_rd_r=0R3EGEJM92YBNVN0B9E7&pf_rd_t=36701&pf_rd_p=2079475242&pf_rd_i=desktop)

However now I do not get any lightup from my dash osx and battery lights. The temp flashes and oil still lights, but not the others.

There were 3 wires from the old setup.

Large white (12v)
Yellow
Black/white

To the new alternator plug I did:
1st (furthest from charge lug) not used
2nd pin Sense (middle pin) to yellow
3rd pin. (closest to charge lug) to black/white.

Nothing connected to the old plug's white (12v)

When I crank it on I get 14.5 volts w/out much running.

13.6 or so w/ all lights, radio, fridge, AC, etc... so I'm at least getting a charge out of it.


What did I mess up?

[snwbrdr435]

Have any pictures. Did you mess with the blue wire under the drivers seat?

[insyncro]

FYI, the 3.6 and 2.5 alts are different.
The 3.6 being far superior.

[termuehlen]

I do not have the specifications for your exact alternator. When I did my upgrade, this is how I wired mine:

For the 23700-AA370 alternator, the pin closest to the 12V+ Post is connected to the alternator light in the instrument cluster, the middle pin is connected to 12V+ field wiring to "sense" the voltage, and the last pin is unused (farthest away from 12V+ Post).

I also do not know what your "yellow" and "black/white" wires are connected to. The pin closest to the 12V+ post should somehow be connected to the VW battery/alt light connection on the instrument cluster. This is usually a blue wire located in the engine compartment electrical box (on the front engine compartment wall, drivers side). You should be able to check continuity from the wire at the alternator all the way to the connection on the instrument cluster. The middle pin should be 12V+ when the engine is running (providing the "sense" signal). You should be able to check easily.
_________________
1988 Westfalia automatic Subaru OBD1
1986 syncro tintop wbx

[MrTibbs]

Appreciated the feedback. It sounds like I'm on the right track.

Pin closest to the charge lug = gauges
mid pin = sense
last pin not used.

I'll poke around in the engine junction box to see what connect to what (engine swap was done before I purchased it to see what is up)

2nd Question. In the orig ej22 setup what was the purpose of the thicker white wire that was constant 12v?

[MrTibbs]

Found a pic of the pinout of '92 ej22 alternators to help others who run across this.

After looking at this I think I have an idea where I screwed up. Will report back.

[Syncro Jael]

See if the info on this thread will help answer any questions.

http://www.thesamba.com/vw/forum/viewtopic.php?t=601176&postdays=0&postorder=asc&start=0

http://wilbo666.pbworks.com/w/page/39441708/Toyota%20Alternators#AlternatorRegulatorSTerminal
_________________
1987 Syncro Westfalia Hightop - NAHT
Subaru EJ25 Forged Frankenmotor, Triple Knob.
Jael = (Mountain Goat)

[MrTibbs]

Alright, so here is where I am, from the pic above:

I took the old B+ wire and bolted it to the alternator charge post.

12V+ switched ignition wire to the SENSE post

Idiot Light wire to Idiot light post.

With the key "ON" position idiot light does not light up.

However if I jump the Idiot light wire to ground it does light up.

Is the idiot light pin supposed to provide a ground when not running?

It would make sense that when the alt is charging and providing +12v from each side of the circuit (alt idiot light pin and from + dash, creating a dead circuit) nothing lights up...

[ScottShelley]

I recently did this upgrade. If you ground the idiot light wire it lights up because that is what it is supposed to do. The idiot light terminal at the alternator provides ground when not charging and voltage when charging, which essentially cancels out the voltage at the power side of the idiot light, turning the light off. Put and ohm meter or test light on the alternator terminal, when not running and see if it is grounded. Now start the engine and you should have alternator voltage at that terminal. It sounds like your alternator is working from the voltages you describe. More than any other part, I have had something wrong with an alternator straight out of the box.

[MrTibbs]

Alt, is definitely not grounding on that idiot light pin then. Glad I'm not crazy in the theory of it.

I'll survive w/ just the voltmeter I have connected to monitor everything at the front.

[MrTibbs]

Finally sorted.

The orig 'upgrade' alternator from EBAY was listed incorrectly (was for the 2.5 engine) and was faulty (idiot light pin would not ground), and also did not line up properly w/ the lower pulley.

Sent back for a refund and got a proper one for a 3.6 10+ engine (23700AA620) from another vendor.

After a slight case grind, hooked it up, turned the key, oxs and bat light warning lights were back!...fired it up, and bam 130amps of charging delight.

Thanks for all the help folks, and glad I got to learn a little bit about alternators along the way.

While waiting on the replacement I also took the time to redo my rear bumper w/ a swingaway to carry more precious fuel.