Hey! I just built a Bremote v1 from a kit and everything worked fine. I havent foamed it yet but its closed with epoxy.
While testing it, setting up RX and VESC it showed UU error code, undervoltage so I plugged it into the USB cable, which works since it shows up as “waking up, going to sleep” in the serial monitor in Arduino IDE.
Anyone have any idea what could be going on?
If battery is disconnected it wouldnt even turn on and I can write data to it.
Does the red led on the PCB light up when USB is plugged in? Otherwise the charger IC is broken…
Yeah it does light up! I got the bottom cap open so I can see the PCB but cant reach the battery. Suspect the battery might be shot. Or can it be something else?
Battery (14500) shows 4.184v so fully charged 
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Now the board makes this faint buzzing noise (maybe it always did?) when plugged into usb so I snipped the battery off and when trying to turn on only the dot between the 2 characters on the display blink a few times. Serial monitor only shows: turning off (or something similar), what does the blink means? Did I mistakenly brick the board?
If the light is on it should be ok, without a battery attached it blinks a bit, that’s also normal
Did you change any settings in the config of the TX? Maybe the battery full/low values?
@ludwig_bre Thank you! of course thats what I did, I mistook internal battery values for the tow boogies battery 
So now everything works?
Everything works! Unrelated to previous issue is a consistent E4 error but theres no connectivity problems even when walking quite far away.
PS. Thanks for making this open source/kit/remote I really enjoy people making/building