I have an MICS with a 6 port fiber expansion card installed and running. Currently there are 3 0X16 Station Modules and 2 Analog Modules on the fiber. One of the analog modules is no longer being used, and I think may even be faulty, as it has its power light flashing. Anyway, I have the option to simply do a backup, then install the new 0X16 in the last available fiber port and power it up. What I am wondering is if I can disable the unused Analog card, power it down, unplug the fiber and swap the modules. After that I believe I would have to go into maintenance and re-define that module as a 0X16, power up the new module, then Enable it. I'd like to do this with the system power still on if I can. It's been running on the wall a long time.

If the ASM is dead unplug and toss it.
Plug in the new 0X16 fibre cord in the next available port working upwards.
Power up 0X16
Program

Mickamg - I try to take the SAFE way and what you described is the SAFE way.

Question is: You have TWO analog modules. Is the second one piggy backed off the first one and using just ONE fiber expansion port?
IF YES - THEN, which one is the BAD unit.

If they are NOT piggy-backed, then no issue.

IF they ARE piggy-backed then........
If the second unit is bad - no problem. Again I would take the safe way and disable the ASM module (that would disable both) then remove the bad unit.
and then re-enable it. And yes a backup would be good. I just don't know if it would care or care less when it suddenly does not see that second unit.

If the first unit is bad - as long as it is not dangerous, just leave it be and your second module will still have the same config.
IF you want to take out the first unit, then your second unit would now be your first and you would need to switch all the programming.
If you re-use the amphenol cable for the second unit the phones should still be connected, the programming would change with the new extensions.

Not being on site I can't say for sure, but what you say sounds good otherwise.