Fuel Injector Circuit Diagnosis (Regal): Description
WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2003 Pontiac Grand Prix, 2003 Pontiac Bonneville, 2003 Chevrolet Monte Carlo, 2003 Chevrolet Impala, and 2003 Buick Regal. However, it is still accessible from the selected car via links, so may be relevant.
The Powertrain Control Module (PCM) enables the appropriate fuel injector on the intake stroke for each cylinder. An ignition 1 voltage is supplied directly to the fuel injectors. The PCM controls each fuel injector by grounding the control circuit via a solid state device called a driver.