Iām getting a vesc tool error that says āDetection failed. Reason: -11.ā I checked for faults but there are no current faults. It did register a low voltage though but it was really strange. It listed input voltage as 6V and 2V. Iām using a makerX dual vesc which was previously working just fine.
Ohhhhh I randomly also found some tubes for bergsssā¦ I think those should also fit ??? Anyone @mmaner what say you ??
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They will work with Berg tires in 6 shooters but not the clever tires. Sorry.
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It should fit.
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I burnt mine on one side during first setup and it shown -11 during detection. Now one side keeps blinking red and heating up. Maker-x dual vesc
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How far into detection were you able to get? I was able to almost get to the end of hall sensor detection when if reported the failure. Nothing out of the blue as far as I could tell. Everything ran smoothly during detection so Iām at a lost as to why this would happen.
At the part where you set wheel direction it let out the magic smoke
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Ahh i donāt think our situation are the same then. Nothing hot or smoking as far as I can tell. Everything still works well except for the fact it canāt seem to detect properly. Currently switching out components to eliminate what it could be
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Hmm so swapping to a different 12S battery seems to have resolved some of the programming issue. I was able to complete detection and programming although I was getting bad start performance for sensored FOC for some reason.
Could I get some help diagnosing poor FOC and 10s battery issue? As far as I can tell for the 10S, voltage is correct and not low
Would be a good idea to open it up and check the mosfets. If i wasnāt watching it i would not have been able to tell that it let out a spark. Also seller does not recommend running 12s at all.
All i know about mine is that it had big trouble trying to spin the motors outside the detection phase of the wizard
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Also check for solder ballsā¦ i found quite a few on mine
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I think the main concern for 12S is voltage spikes past 60V. If you can manage that, thereās nothing wrong with running 12s. Thatās what I was using for the longest time although Iāve switched since then 
I figured out the issue. Wasnāt mosfet related as mosfets didnāt heat up and motor movement was very smooth except for the start/detection portion. This vesc performed flawlessly for a long time until I transplanted it to this new build. As usual, the fault codes were a hint
It ended up being a low power issue. Hooked my DaVega up and discovered that voltage bounced around wildly. Wish I figured it out sooner but the culprit was an improperly seated (I think, I still need to investigate this) loop key. After running the board for a 10 seconds power shut off. Pulled the loopkey and it was burnt. No where else in the system was even warm to the touch.
The thing is though, I could have sworn I shoved the key as far in as it would go. Maybe during soldering I might have pushed one side of the XT90 in and it didnāt seat fully.
Once I fix that, hopefully detection will go well and Iāll get smooth starts in FOC. A weird side note is that previously, this vesc wouldnāt play nice with DaVega but it did today
I had a conversation with a friend about this the other day actually, if you canāt pry off the solder ball, it shouldnāt be an issue unless itās an actual short. Were you unlucky and got an actual short? 
Same pictures again. You see what i see. And what voltage can possibly spike at 0rpm on a test bench?
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I think sparking can produce a voltage at 0 rpm 
Yeah I see a blown mosfet although not sure what could have caused it though. Thatās a bummer though. Luckily my makerX still looks fine
Did you ever figure out what went wrong?
Still no idea. The whole line of mosfets is blown and i think the drv with it. I got 2 trampa vescs now to mount
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Noob question:
If you blow something up, you start by detecting unwanted shorts etc on your circuit. Letās say Your Mosfet is shorted.
You replace it. But can you be sure that the electric components around it, like capacitors, resistors still work properly?
Like, would it make sense for @Athrx to replace the Mosfets and DRV chip?
I suppose its like in the real world: if a house blows up, a few neighbourās might get damaged too, so you have to check a certain āradiusā around the dead chip for defect components?
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Basically itās a judgement call based on time, effort and cost: Will it cost you more time and money to try to fix it, or just chuck it in the fuckit bucket and replace with a new one?
Of course, it depends heavily on your skill at fixing, and your equipment and available supplies - DRVs are difficult to replace unless you already have the skills and equipment to do so, becuase theyāve got a big solder pad under the case that you canāt reach with an iron.
When doing such a repair, itās best practice to test every part of the circuit that you reasonably can before powering up again. That means not only the passive components on the board that you mentioned, but also your motor, battery, and all the connections in between everything. Failures like that are very rarely without some obvious external cause like a shorted phase or a solder blob where it shouldnāt be, and if you donāt find and remove that issue you will immediately fuck your repair again, possibly doing more damage than before.
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Alright!
You need a hot air gun for these SMD chips right?
So, you would adwise to check every component possible on the VESC and also look at the physical condition?
Yes to both.
You can also do SMD rework with a hotplate/oven/IR, but hot air is common.
Clean Everything. Remove all that thermal goop and scrub the whole thing down front and back with IPA and a toothbrush, then inspect. Then take a multimeter to it and check everything you can. Some stuff canāt really be checked in situ and unpowered, but looking for shorts where they shouldnāt be, or open circuits where they shouldnāt be, is a good start.
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Assume everything from that component upwards is bust. Letās say resistors, ceramic capacitors, diodes, inductor coils and mosfets are easy to spot. You measure them and they either work or they donāt. But on components like the drv chips itās a bit complicated. They are expensive to buy replacements for and hard to solder (even desolder the old one) without some tools and knowledge. Itās not something you learn in 10 minutes from a youtube video and you probably only even need to do in once in your entire life.
Thereās a good diy or buy video for the vesc 4.12 (i think?) From greatscott and it shows what a pain in the ass it is to get some of the components in, even for an experienced person.
For the maker-x esc, the design is somewhat smart. Mosfets and most āload bearingā components are on the bottom pcb that screws on the heatsink, and small smd components and stm chips (the expensive part) are on the top pcb along with connector ports. The seller has sent me the bottom pcb part at shipping cost to me in hopes that the drv is not bust. Weāll see how it plays out. For now i have a fried antispark and an unusable dual esc. For the price iām not even too mad. I knew it was a gamble 
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