I have a 2004 Fadal 3016 (AC drives) that will periodically give amp fault 18 on all 3 axis during start up. It's a sporadic issue and once it finally clears, the machine will run fine. If the machine will perform a cold start, it will run fine without fault. Typically, if I get a fault on start up, if the machine sits for 15 minutes or so and I restart it, the faults will clear. I've confirmed that I have power to the amps so the fault line, solid state relays, and power side of the amps is functioning fine. Looking for where I should go next in diagnosing this problem?