As the titles suggests. I have confirmed it is a problem with the console because the joycon charges when attached to other consoles.
I did get it to charge briefly by charging the 6 pin IC on the back of the board (VVIC) but it stopped charging shortly after. This is the IC that regulates the charging and handshake of the joycons as fair as I know. The only other time I have had an issue with this particular IC was on an OLED but unlike this console the OLED didn’t charge or recognise the joycon. This console recognises (handshake) the joycon but won’t charge.
I haven’t had to troubleshoot a problem like this many times before but so far I have changed the rail on the console and the IC mention above.
I have seen other posts suggesting this could be related to the Fan circuit but the fan seems to operate normally.
Is there any other areas I should check out?