NEXIQ CAN 3 TO CAN 1 CROSSOVER - 406004. Allows older scanner and scanners only capable of reading J1939 to work on the newer Paccar vehicles. CAN1 to CAN3. CAN3 to CAN1. Diagnostic Crossover cable for your 2016 and newer Paccar - Peterbilt, Kenworth, Western Star, and Volvos among others - with Cummins engine.