Hello group!
I have a 2001 3200gta preobd (the 3 pin ecu connector!), and to ease CEL fault
tracing, i built my own
SD tester for the engine ECU. To make sure that during engineering stages, i
will not brake anything, several ECU's have been bought.
On the test bench, electronics and software could be designed without the pain
of hiding in the car for many many hours. Well i must say,
the results are stunning!. Using a dedicated notebook running DOS (oh yes), now
i can:

-read all DTC (engine trouble codes) for a 3200gt and reset them (reasons for
CEL)
-read realtime values from ETM (pedal setting, valve setpoint and feedback)
-read realtime sensors (CW and air temp, pressure sensors).
Unfortunately, not the ignition coils (yet!)

Release 1 is upcoming, i almost have the Airbag ECU under control:

-read DTC
-reset airbag light if sensor failure (sorry not the crash data)

Currently, the suspension controller is on the test bench, to read what causes
the error light. (but this is a difficult one).

Just to ease on my ecu investments, i will sell a few, so if you are interested,
let me know.

picture of the interface here:
http://img4.imageshack.us/img4/2057/interfh.jpg

demo of the software here:
http://www.sendspace.com/file/hpxqfv

Each owner of the mini tester gets free software updates as long as i own a
3200.
After all, its for helping fellow 3200 owners,

rgds
Marcel
Netherlands