how to diagnose a troubles in a hashboard?

Greetings, well in relation to the title I would like to know how to do it because one of the hashboards of my antminer s7 generates conflict with the boot to mine. The hashboard turns on and behaves normally (like the other cards visually), it turns on the light of the normal hashboard, but the miner hangs up when this hasboard is connected. I already tried changing the power cables from one hashboard to another, already tried too change the cable from the BB to the hashboard, and nothing. During the first 5 minutes you can access the miner interface when this hashboard is connected to the BB. After that, the miner hangs up and the interface can not be accessed.

In the interface, show Asic 45 to 700M (default) on each hashboard, and all show 6 groups of "0" and none X. I tried leaving 1 hashboard connected at a time, and 2 of them worked well (hashing) and 1 of them behaved like the others but not hash, but this time the miner did not hang last 5min, it was just 0 Gh / s on the "miner status" page.

I have also measured the input current in the PCI-e ports of the hashboard, and it marked around 12v.

Does anyone have an idea what it could be?