2004 has max lockup with the transfer solenoid driven at +12V, min at 0V.
2003 is the opposite- no juice and it locks, +12V to disengage.
I successfully used an inverting solenoid driver to invert the signal,
that is, turn the 2003 signal of little blips to 0v for a little lockup
and longer blips to 0v for more lockup into little blips to +12V for a
little lockup and longer blips to +12V for more lockup.
(In reality it is a 50Hz pulse-width-modulated signal).
The outcome is about what I thought- it is driveable, doesn't seem to
bind on tight circles, and it is sufficiently locked when I need it to
be (still some snow about for testing), but it isn't quite right.
In D from a standing start in snow it will spin for a moment then engage
with a bang, and if I drive through snow slowly it will bang on and
bang off. Fortunately it engages nice and smooth in 2 and 1, so I can
live with it.
On wet pavement, planting the gas from a standing start works OK with no bang.
So, it's not 100%, and I need to drive it a bit to make sure nothing
weird happens, but for my 200,000 mile subie I can live with it.
Of course some of the symptoms might be from a trans that has seen some
torque bind, or perhaps the clutch baskets are grooved a bit. Not in the
mood for further teardowns this season, though.
Edited by CNY_Dave, 27 February 2013 - 09:49 PM.