Laptop turns on for about 5ish seconds then turns off again

I have a broken dell latitude 7280 that I'm trying to repair, I'm not too sure why it keeps turning on for 5 seconds then turns itself off when I try to boot it, I have a feeling it might be the battery but I just got a new one for it and a new motherboard as the previous one had tpm issues it could also be the ssd but I'm not sure, there is a high pitched sound around the main charger and battery cable tho, the keyboard lights up and everything fan spins but then it just dies, I can do this multiple times in a row and it will do the same thing, so far the only diagnostic light I've got is solid white which I'm pretty sure means the battery is above 5% but I just need help on what the problem is to fix it or at least get it to go into bios ( it also does the high pitched sound when it's on charge only)