[ischmitz]

The injector wiring is pretty simple. Inside the ECU is an output stage that provides GND on pin 14 and 15 of the 35-pin ECU connector to fire the injectors. The injectors are two-wire devices with an internal coil. One side of the coil sees +12V once the ignition is ON and the other side of each bank is connected to either pin 14 or pin 15 of the ECU.

With the ignition ON and engine not running (duh) pull one injector connector and confirm +12V on each socket of the connector. Both sides with read +12V. If not you might have a blown fuse in the engine bay or some other wiring issue. See here for how things are wired. Pin 14 and pin 15 are internally connected inside the ECU. Pin 18 and pin 35 are powered by +12V as soon as the ignition switch is in ON or START position.

This configuration is called a low-side switch.