the lipo pouch inside might be puffed
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Could be, it sounds like pressure escaping lol. Like⌠A ziplock full of air being squeezed with only a teeeeney tiny hole in it.
It sounds kind of electrical-y but I guess it could be the lipo 
I assume itâs time for it to hit the bin?
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its best to get a new one asap, if u donât mind the size i suggest those 18650 power bank case and just put whatever largest mAh cell u can find in it 
if cell goes bad, just swap them out instead of buying a new one
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This concludes our series âLife Lessons You Should Definitely Ignore With Albertâ
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Moving the discussion here so that we donât derail.
I think the âgenerallyâ may be a bit of an overstatement. I definitely accidentally swapped CANH and CANL several times and never had any issues. I tried googling it and I havenât been able to find any evidence that it should lead to damage. Also, looking at the datasheet for the SN65HVD232DR that you mentioned, it has the same limits for both pins, so I wonder how it could get damaged as a result of swapping them. Are you sure?
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Ive killed at least one reference 4.12âs canbus chips via criss-crossing the wires. Based on the CANH - CANL = 3.5V - 1.5V = 2V(in spec), I assumed that reversing the lines resulting in CANL - CANH = 1.5V - 3.5V = -2.0V (out of spec) honestly thought that was enough to kill the chip, but I donât know how gracefully the chip handles errors. 100% unsure, couldnt prove a thing.
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it was
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Normally I donât post my repairs but this surprised me so much that I had to 
This unity came as water damaged with only one motor working. I was expecting some corrosion between pins, not allowing things to communicate thus one motor not spinning. I opened the unity up and saw three main thingsâŚ
The first one was this kind of corrosion or whatever it was on the DRV8301:
This was definitely the thing causing the motor not to spin
The second issue was a lot of corrosion and oxidation on the antispark mosfets:
And the last issue was a blown accelerometer, not sure how it blew but it just did (visible hole in the package):
I did not try to solve this because of the accelerometer not being used. It wasnât causing any shorts on the 3.3v rail so I just let it be.
The antispark was solved pretty easily, just cleaned it with some isopropyl alcohol and it was looking brand new. I thought that the DRV will be the same. After cleaning, it was looking promising, nothing blown. Then I took a brand new unity just to make sure and I saw it, one of the pins was missing:
(new one on the left)
New DRV chips are out of stock almost everywhere, so I started wondering where I could get a vesc to get a DRV transplant from. Just out of curiosity, I plugged the unity in and saw the red LED flashing. That means that there are some faults. I checked vesc tool if it was reporting any errors and I saw this:
This means that the DRV is still alive, and it was giving me hope that fixing that pin could make it work again. I checked the datasheet and the broken pin was pin 29, âPVDD1â:
Power supply pin for gate driver, current shunt amplifier, and SPI communication.
If this pin is responsible for powering the current shunt amplifiers, then it explains the error above. I was thinking that some remains of the pin should be inside of the chip package, so I took out my knife and started scraping the plastic off. Soon I scraped enough that I could see ~0,5mm of the pin and I tried to put solder on. The pad underneath the pin was ripped off the PCB, so I had to find somewhere to connect the pin to, Fortunately, that was pretty quick because right next to the pin is a capacitor that is connected to VBAT, exactly what we need.
Here you can see the exposed pin, as well as the capacitor right next to it:
This is probably the best photo of the wire connected that I could get (I donât have a microscope):
After this, I plugged it in and the LED was no longer flashing, thatâs a good sign!
Then I connected a motor, crossed my fingers, and tried to run a detection⌠and it WORKED!
Here is a screenshot of a 50A open-loop run:
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Looking for some more players if you guys like fantasy football come join us
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Thatâs badass.
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Thatâs some impressive diagnostic work. This is going back into service?
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Joined!!! San diego sk8 and b8!!
Donât your eyeballs bleed with that theme on?
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I need a high contrast theme, my vision isnât very good unfortunately.
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I appreciate when discourse forums incorporate high contrast themes like this.
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Iâm not sure this was the intention of âI CANT FUCKING READ THISâ but Iâm glad it worked out for you
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Oh I see, I understand now.
I think others have had weird exchange with that dude regarding his sales
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Does not ring a bell
Nah this kid is under 18, and even though I had hoped heâd grown up heâs clearly full of shit. Made many many terrible sales threads, several insulting and/or self important DM âoffersâ for other peoplesâ sales.
Also âMath professorâ, give me a break. I know Americans throw that word around but come on now. He probably solved a simultaneous equation for a 15 year old cousinâs algebra class and called himself prof
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