Hi I have a guard tech 500 series alarm and on the panel it's shows the letter A which it says is a fuse fault. I have tested the panel on the mains and outgoing also the other side of the transformer. Tested the fuses and everything is fine, is there any other fuses hid or anything else why it would say a fuse or mains power fault.

John, January 2017

I'm guessing you tested, looked at all the fuses while looking at them in situ

ssss, February 2017