Power Transistor
WARNING: This page does not describe the selected car, but rather 9 other vehicles, including the 2000 Nissan Xterra, 2000 Nissan Sentra, 2000 Nissan Quest, 2000 Nissan Pathfinder, and 2000 Nissan Maxima. However, it is still accessible from the selected car via links, so may be relevant.
Faults in power transistor should set a DTC P1320. For testing procedure, go to DTC P1320: IGNITION SIGNAL in appropriate SELF-DIAGNOSTICS article.