I am also battling to get comms with AM5. i purchased a Growatt spf 6000 ES plus inverter so hoping the Comms protocol should be the same as the 5000? tried CAN to CAN connection with 4/5 pin RJ45. no good.
Are you saying add pin 1/2 to RJ45 so 1/2/3/4 straight cable? Then into CAN/CAN.
I only tried L51 protocol - so will try L54 once Cable is correct.
Your reply will be much appreciated