86Marlboro
Member
I have a 2012 Mack GU713 VIN#: 1M2AX04Y4CM011138. I cannot connect to the J1587 data link communications. I can get into the J1939 however. I have checked the respective fuses and voltages on the comm port. My J1587+/- wires ohm out together showing connection, I have 1.5 V on my + and almost nothing on my -. I checked the terminating resistors beside the top fuse panel and it showed good 120 Ohm resistance. Not sure where to go next, my radio doesn't play. It lights us and says "Check Amp Fuse" which is F10 that corresponds to the comm adapter. Not sure where to go/check next any advice would be appreciated.
Attached are snips of schematic for circuit.
Attached are snips of schematic for circuit.
