fanuc 11 "L" error and masterboards revisions

[guhl]

My old masterboard A16B-1010-0330/11A comes to senses only after heating of the part of PCB and operates. Axеs running.
Installed another masterboard A16B-1010-0330/10A shows "L" and on screen I see "PC PARAMETERS LOAD:END", though all additional PCBs(memory, etc.) works fine.

In what difference between 10A and 11A revisions?

[memoryman]

usually the board revision # only matters if you replace a board with an lower #, as you did, but I have never had a problem doing that. Did you check for jumpers? Was the /10A board a known good one?

[guhl]

I think I know what the difference is:
on 10A two driver ICs are soldered, and on 11A they are in the sockets
this masterboard doesn't have the jumpers
I don't 100% sure that this PCB is a good one. now try to test it