When the ATi is powered up, why does the tester hang up and the message displayed “loading new program”, after restarting 2 or 3 times it boots properly?
This is due the RUN connections to the remote port being stuck in the ON position.
In one factory some years ago the factory cleaning person pushed a foot switch under the table to sweep the floor every night. In the morning, the ATi would not switch on because the switch was jammed on! When the operator sat down and moved the switch, everything was OK!
If the switch is sticking on, or wired incorrectly, and the ATi is passing all self tests with the remote port disconnected this is likely to be the issue.
To verify this please check the following:
Check the resistance of the foot switch and cable in the open and closed state with a multimeter.
This should be >10M Ohm in the open state and <1 Ohm in the closed state (foot down).