One user has problem to read and write edc16cp31 with fetrotech ecu programmer, have three tries with three different cars and all three don’t work put X on mb 16cp31 (shown as below).
Solution:
Use this top pinout, pay attention to the gpt wiring, as I found the colors on the pinout I used do not match numbers. Opposite to each other.
Work
On pinout one, no need for can hi/lo just k line.
In addition:
Fetrotech EDC16C2 Mercedes pinout :- please also connect CANH + CANL.