Truck Repair: fault code, cummins engines, volvo engines

Question
I have a 2001 5.9 cummins in a school bus,i have a code pid100 (low oil psi).Dont fool much with cummins engines,any help would be great.

Answer
More then likely your oil pressure sensor has gone bad. i know alot of the sensors ive changed in the isx and volvo engines when you unplug that sensor it will have oil in the the electrical plug. Regardless though thats the first thing i would change if you dont know where that is get me a serial number off your engine and i will look up where the location is for you.