I've been fighting an intermittent -AIP1 Alarm Ram Error- on a Hitachi Seiki vk45 seikos m3 control for the past few weeks. I have replaced the SAMS1 board which helped for a while but the faults came back. Mori Seiki had me replace the NUMC board along with all the yuyu software. The fault went away for a few weeks then it came back again. I have even replaced both power supplies. Every 6 to 8 hours the machine will stop in mid program with no faults. The operator will try a return reset and it will change tools and sit, still no faults. The machine is then powered down and at power up the AIP1 alarm Ram Error comes up. By the time I check some connections and voltages and power up and down a few times the faults clear out and it's business as usual. Sorry for such a long post but I have run out of ideas. I’m new to this site and semi experienced with cnc repair. I would appreciate any thoughts or suggestions.
Thanks in advance for your help.