The Mitel 200 ICP controller (in its various forms) is fairly resilliant.  While I've seen controllers go bad and cause vague errors like 'distortion on trunk calls,' I haven't yet seen a controller that simply won't boot -- if the power comes on.

 

I mean, I've seen controllers that won't boot plenty of times, but it's always been caused by one thing: the modem.  Mitel's answer to a controller that won't boot is to systematically unplug cables from the controller because something is probably creating a short.  I've never yet had to unplug anything past the maintenance port to get a system to come up.

 

While we generally say a 200 ICP can take up to 10 minutes to boot, we generally see them come up faster than that.  A good indicator as to whether or not a system is going to boot is to look at the disk drive light, which is above the COM ports on the left of the face.  Here's the sequence:

....it's generally that easy!

If you are trying to upgrade a controller and things go terribly wrong, you should be able to put in an initial install flash card to the face in order to recover the software.  This will delete the customer's database, but it should make the system bootable again.