16V, ECU voltage checks at ECU:
92-95 SideKicks and Trackers
GM-GEO VIN, code #6 (engine)  [ code U is 8 Valve ]
Suzuki VIN for engine is 0.  Then count injectors.  ah , its got 4.                                    
G16B Engine USA 16 valves only.  MPI
The Suzuki VIN does not tell you if engine A or B (8v or 16v) just code 0.
This ECU is 16 valves  MPI 4 injectors. (side draft Throttle body takes only a glance to see)

The ECU is a computer, or computing controller, for the hardcore and is OBD1 USA EPA rules. (etc)
I have few answers for the ROTW, (rest of the world) your stuff is UNIQUE. (eg. we don't have the IMMO option here)
This ECU is NOT programmable in any way.  It has a deep BURIED ROM Firmware coding, sorry no FLASH memory here. (hacks are very rare, it's no HONDA)
As such, it functions, by the basic rules of all computers.
  1. No power , then its dead.  Easy huh, if you do not have DC power to the ECU, the ECU is ,well,  DEAD. (it will run with out  the memory feed, DOME Fuse)  
  2. GIGO , Garbage in , Garbage out.  All computer fail to work or compute correctly, if you lie to it , or as in this case the SENSORS ARE FIBBING (wrong)
  3. If you hot wire any computer out output and you blow up the drivers inside the ECU ,well , there you go... you now killed and actuator  (injectors ,VSV or worse)
  4. Never hot wire any ECU or any thing connected to it, our you will be paying Cardone  $400 bucks for a new ECU.
  5. This is not 1960,  stop hotwiring and WIN , (sure do the starter solenoid, or tail lights) but do not hot wire the EFI system parts.
  6. Do not ever ground out , pin B6, or risk ECU damage.
  7. The ECU will almost NEVER blow up and INPUT. (they are protected very well)
  8. The Pre 96s,  love to blow up CAPACITORS (rubycon junk)

ECU PINS: (called Pinout)  For colors and locations click the links.

A connector has 22 pins.
B connector has 26 pins  fatter/thicker pins too , for power !

Conditions: Hot engine, normal battery voltage at rest 12.6 volts, min. at mild ambients.

Popular and and critical pins on the ECU . key on or running  (a short list)    See them all here.

 Name  keyon
 Idle Switch
4-6v off idle  ( if switch fails , all idle controls are now OFF LINE)
Refr. 5v voltage
Check it at the TPS (gray-red) , typ. 4.75 to 5.25vdc , if  not at spec. ECU is bad or line is shorted
varies from idle to WOT.  See all sensor voltages here and below. IF stuck over 4v the ECU will cut fuel cranking
varies with air flow MASS , induction air , MAF power is +Battery voltage at all times
varies with Air/ fuel mix ( mid point is perfect)  (this is not a critical sensor, car runs with it disconneted)
varies with Air temperature. 400 ohms hot. typical (measure ohms only disconnected key off) (fine tunes AFR ony)
vaires with coolant temperature.   300 ohms hot 180F coolant (ditto , above comment)  may be 3000 ohms cold. (typ)
Main Relay Enable !
never changes, unless some one hot wires the fuel pump relay and blows up ECU DIODE D102, a $400 FU?
Power  feed
A12 /13 is main power relay power, A1 is dome fuse ECU memory power. (not critical)
Ground (power)
 POWER GROUND, .  0.5v or less to body (or battery minus lug, key ON)  if not , bad car wiring.

The CEL lamp will  glow EVEN, if power and ground pins above are GOOD. (even ECU parked on a work bench top)

Missing pins on car ECU connnectors, are normal, for  example the A/T pins , on a M/T car!   (automatic transmission or manual)

All  voltages are taken by back probing (needles) the ECU connectors, nothing disconnected and car battery charged to 12.6vdc rested.
Running a California ECU on any Federal harness (or the reverse) will cause malfunctions of the EGR and will  throw DTC code 53.
There are more critical pins, to start and run any engine, for example CMP signals.
All pins and all voltages are contained below,  and here.

FSM Pin page 1

FSM Pin Page 2.

The Giant schematic for this engine EFI with notes !, is here.

V: 2