Posts: 492
Threads: 69
Joined: Aug 2020
Could there be a hidden 6 or 9 pin OBDI port somewhere up in the dash area? All I see is the little flat port right under the key.
Brad Aden
2003 Newell #653 Quad Slide Cat C-12 engine
Towing 2020 Grand Cherokee Summit
St. Louis, MO
Posts: 5,751
Threads: 493
Joined: Jul 2012
detroit and cat neither use obd. it takes a special scan tool. the rectangular plug is what newell used in that vintage. the silverleaf will work on it and you can read codes.
tom
2002 45'8" Newell Coach 608 Series 60 DDEC4/Allison World 6 Speed HD4000MH
