Note. For circuit reference, see DTC P0201 schematic.
Circuit Description
The PCM contains a General Field Effect Transistor Driver (GFD) that controls the 8 fuel injector drivers. The GFD is used to determine if there is a problem with any of the fuel injector circuits. The GFD has a fault line for each injector. The fault line goes high when an open, short to ground, or short to voltage is noticed in an injector circuit. DTC will set when the fault line for an injector is high.