What version of cummins are you working on if ISB? Cummins has a plastic covered 23 pin wiring diagram. Bullitin #3666325-02. Has codes listed in cummins fault code and j1587/1939 codes. Hope this helps.
Try Cummins Quick Serv on line. It is a subscripion service, but well worth the money if you are working on a fleet Cummins INSITE, is the the factory PC based software for the 5.9 ISB engine. Its a little on the expensive side.