You gotta put some effort into this pal. Read, search, experiment, something that isn't just sitting there with your mouth open expecting to be fed. Not more than 2 minutes ago I was reading a post on this very forum, same section even, why blindly plugging in your dash would result in smokey karma....

Ive read if you flash the dash with 1.10 or 1.14 and not 5.5.5 you can use some of the tools like xaioflasher or iap to flash the BMS to 1.34 but I've never tried. What I know works for sure is using/flashing with st link and stvp directly onto battery and flashing 1.3.4 fulldump hex. Then when you ...

On my SNSC 2.3, there was no 5v line from the ESC, only the 36v, voltage conversion for brake and acc was done via iot box/dash. What I did, to connect a g30 dash that uses 4 wire, was cut the cable coming from the ESC, and (connections are from esc to dash) wire the 5v blue wire from esc to the red...

Make sure the C2 capacitor is removed. Other than that, if the method works for one but not the other, it's likely a hardware issue, possibly the STM chip, I'm sure the cheap Chinese clone dash's use cheap chine clone chips.

Its 100% the firmware, 8.1.8 or what not. The way I fixed it is to open the batt, connect ST-Link , open STVP (stm8 flasher), and flash fulldump 1.3.4 hex. Then, flash the ESC with 1.2.6 CFW, enabling stealth mode and error reporting level 3, that will get it working normally and avoid an error code...