Hi,
It may be rebooting. you have to console the IAP and monitor for some time. you need to observe the master beacon messages. if possible please share the output of the boot messages, we can identify information related to your issue.
BTW, is the internet available to the IAP. if so it may be trying to contact the Aruba Central :)
if it is continuously rebooting there may be some issue with the hardware.
Please feel free for any further help on this.