The solution is this, connect, then scan to diagnostic connector but not to USB, open the Cummins insite and push connect, when the Insite begin to connect, immediately connect the USB and ready…. Tryed on 3 trucks already that are 2005 and older the connect thought J1708 it says engine 128Īnd when doing the J 1939 test on them it says something like data error Some things odd2006 models connect through J1939 and works. On truck does not even get the engine and the others only couple line and very slow, might be some thing with them trucks Select retry, cancel or help for additional troubleshooting steps The correct communication protocol is selected The cables are between the datalink and the ECM are properly connected This is the error 5204 popped up when connect Prostar 2005 with cummins engine:Ĭommunication between the datalink adapter and the ECM could not be established. With DPA5 adapter, i try to connect with Cummins insite and i have error code 5204 or only no connection and not blinking the leds Here you go… How to solve Cummins Insite 8.1 Connection Error 5204 5202 5201 5200 How to solve Cummins Insite ECM Connection Error 5204