Hi all, been spending some time reading through this thread trying to see if anyone has a similar issue, and whilst I think people do, there doesn't seem to be a fix.
It all started with the top PSU showing an orange light on the right and green on the left, unit not mining at all. When you turned on just the top one the fans weren't starting on the unit.
The customer service at Cointerra is shocking (and rude), the issue was reported mere days after the 3 month warranty period, I'm in the UK so I'm sure it will cost more than the $350 non refundable fee to get it there (they won't even allow me to ship and return - they make a FORTUNE on their shipping rates I can tell you shipping myself on a corporate UPS account). The breaking point was even if you do that, a 7 day warranty period on the repair; really?! So I'm voting with my feet, I won't be buying anything else from them again and being an advisor to many BTC onboarders I'll ensure they don't get anymore new custom, in my mind they're not far off Butterfly labs now. All that said, decided to self diagnose and try to fix.
The problem...
1) When opened main board had no lights (the night rider orange ones on the board). Not even at startup and no fans.
2) Switched PSU's and ruled out that problem as the good PSU then became the bad.
3) Checked all connectors
4) Tried removing the black and white cables from the faulty board - nothing.
5) Swapped out the 2 boards checking all connections along the way. No leaks found, no bad connections.
6) After swapping boards around we've worked out a board is at fault and as it was the primary board there was no mining. Now the machine is mining on one board so that is an improvement. Interestingly both PSU's need to be on or the unit won't stay online. If you don't power up or power down the 2nd it goes offline (can't access over LAN etc)
7) Now the original problem of the orange light on the PSU is on the bottom one.

No lights on the faulty board at all, not even on startup.
9) Looking at the nightrider lights on the working board D42 and D45 don't light in sequence (on startup D42 does but not D45) so I assume this is why it's hashing at around 700.
10) Only CTA0 displays on the admin screens (before we started I couldn't get to this menu as the faulty board was the main one). On the front of the machine it blinks on Miner 2 as mining.
11) We've not amended or touched the coolant system yet, there appear to be no leaks.
12) We've tried resetting the boards, we've tried resetting the system etc. Firmware is 0.7.6, I tried to install 0.6.32 but it loads but doesn't downgrade.
So.. a board seemingly without power, PSU's seemingly fine, cooling seemingly fine, everything follows the board. Have meticulously checked the board and can't see anything obvious. Any ideas?
Would really appreciate any advice, thanks all.
David
I had a similar issue with my TerraMiner. One of the boards shorted out, resulting in an orange light on the PSU. I could not find a fix for the failed board, so i removed it, its cooling, psu and psu breakout board. To point 6, You CAN run the system with just 1 psu in, you just need to make sure that the small beaglebone power connector is attached to the single remaining power supply. In one of my previous posts in this thread i outline the reapplication of diamond thermal paste, this is a good step to take on your remaining board to get your miner running stable at 1/2 speed. Sorry about your dead board