Has anyone experienced a loss of output from a dual focbox set up?
I have bec power but no phase. They were working fine and then just stopped no lights on or anything. I can’t access them either with the vesc tool. They are 2 weeks old and have run a dual 6374 10s set up with bms for approx 20km
Vesc settings are 60 amp motor max, 25 battery max, both are behaving exactly the same way so I’m hoping its something simple. 
canbus setup? Was one powered off while connected via canbus to a live unit?
Yeah it was. How you doing?
When you power them the lights turn on blue?
no nothing
Is there voltage on the xt60s before the ESC?
yeah voltage and the receiver powers up but no output or anything from the units
Did you try to make motor detection?
Theres no connection at all. stripped both down and they are perfect. nothing fried.
This just happened to me a couple of days ago
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If you powered single unit while another one was off and it’s connected via CANBus I can guarantee that CANBus chip is fried and now it is shortening 3.3V/5V line don’t remember which one. Happened to me before
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This 
I hope you didn’t do this. Its not obvious, so many have done it. Almost needs a warning label on the product.
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Yeah… By removing CAN chip it starts to work, but replacing CAN chip with new one CAN didn’t worked anymore anyway later on the whole FocBox fried so I didn’t looked why CAN wasn’t working 
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So glad i’m not using CAN bus
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Ive got them apart and there is no sign of fried chips. Would a bad can chip be obvious?
I only did this as part of the test process after they stopped. I did then connect each up individually to check my connectors and didn’t think to disconnect the can bus but the problem was there already and I’m hoping I haven’t made it worse
Did you ever figure this out @dareno cause I just had the same thing just happen to me today… just finished a build, did motor detection and all of that and was on my first test ride and in the middle of it all of a sudden after a mile or so I just lost half of my power so just cruised back home (which wasn’t far at all) and one motor wasn’t working anymore… opened it up and only one focbox is on blinking and the other with the motor not working isn’t… I’m not using canbus and running split ppm so can’t be that issue. Took apart focbox and don’t see any obvious burn marks or blown anything on either side. Tried switching connectors to make sure it wasn’t that or something dumb and everything still works with other stuff, it’s just one focbox won’t power on so I can’t even pull it up to connect on the VESC tool to check. What is wrong with it or is there anything I can do?
Hey mate, mine was the dreaded can bus death but it killed both. Yours sounds like a different issue with the same result. I’ve since had drv errors faults on other vesc and you get blinking red lights. I’m sure the focbox would give some indication if it was the drv chip. Total blackout is what happens when the can bus fries. Is it in warranty?
fuck me. No warranty is done. No lights and not seeing anything. Dammit. Whyyyyyyy. Can you see a DRV issue to the naked eye cause I didn’t see any black or anything that looked fried but I am not electronics engineer or expert either? Can you fix that and any way I could check or test for this without power or anything to look for that I can try?