
Originally Posted by
cumminsturbofreak
So I picked up a used MPVI2, and I?m happy to report that yes, you CAN tune the JTEC PCM used for trans control on the Cummins trucks!
However, you will have an issue with failed reads/flash with Baud: Time Out. This is because Dodge put the SCI receive for the JTEC PCM as a white/violet wire in Position 14. The MPVI is expecting to see that SCI receive on position 6, where it is for the gas trucks. For the Cummins trucks, Position 6, dark green wire, is used for SCI Receive for the Cummins ECM. To work around this, remove the green wire from position 6 and move the white/violet wire from 14 to position 6 temporarily. This will allow MPVI to communicate with the controller properly.
Alternately, make an OBD jumper with 14 and 6 swapped for the JTEC PCM flashes only.
Hope this helps someone in the future!