@developeralgo222 said in Duet 3HC Expansion looses Connection:
i will now try factory reset On Duet 3 Expansion 3HC, by setting all four address switches off and board should reset its address and CAN bus speed to default and request firmware from the main board. Tried this and that did not work either ?
I was going to say "put all the firmware files on your mainboard and then set the switches of your expansion boards to 0000, one board connected at a time".
BTW: my RJ11 cable is just a 1.5m phone cable still bundled up from the packaging since it's too long, so length isn't a problem.
After following dc42's advice, double-check physical connections: I have an ethernet connection that sometimes disconnects my Duet from the PC (the clip in the cable broke, so the connector can loosen up, so in your case maybe the connector doesn't fit perfectly due to a shim of plastic or something) and once a Z motor didn't turn because, by moving the connection from the mainboard to the expansion, a connection wasn't set properly.