Please try to unplug the power, wait for about 20 minutes then reboot the miner.
Then please try reloading the firmware: https://shop.bitmain.com/support.htm?pid=00720180209143414844tTh8x2o706B6
Run the miner for 20 minutes after loading.
Please first check the PSU and the controller. To check the PSU you can test the machine with a known good PSU. If you do not have another PSU then check by switching the cables between hash boards. If the issue follows the cable then the PSU may be faulty. Please reply to this email for more instructions.
To test the controller, switch the controller cables between hash boards. If the same hash board shows the issue then the hash board is faulty. If the issue follows the cable then the controller may be faulty. Please contact us for further instructions.
If it still does not work please test each hash board separately to determine which one is defective.
To test each hash board separately: keep the PSU connectors and controller cable on one of the hash boards connected and disconnect the cables from the other two hash boards. With the miner running you can see the status of the connected hash board
Here is more detail: https://support.bitmain.com/hc/en-us/articles/226142788-Testing-hash-board-one-by-one
On the miner status screen defective chips are displayed as “xxx”, “—” or ” ASIC≠60