PS3 PS3 troubleshooting

[Nostars240]

Hi, I've got a PS3 CECHL with VER-001 motherboard. It has GLoD, upon opening it up I've found that someone has bridged all of HDMI port pads with solder. As a consequence, HDMI chip was fried, I've removed it and some other small components. I still get GLoD and no video or audio over AV cable, but putting AV video into one of the audio channels, results in hearing signal as if it's displaying something (I've done it with working PS2 just to confirm I'm not wrong). I've also checked all of the voltages and resistances, everything tells me it should boot fine. Console doesn't respond to power button combinations, only turning on or off, fan test works. Power supply has some coil whine, I've opened it to see if any of the components are obviously damaged. I don't have UART Serial to try and read errors. Could someone with experience and knowledge tell me: 1)Does console boot without HDMI chip? 2)Could it be a RSX? 3)Is there a way to hard reset all settings without power button combinations? 4)Is there any way to forcefully disable HDMI an make it display over AV? Like bridging with some wires or sending some signals to I2C?
Any help would be appreciated, thank you in advance.

 

[turbo9000]

UART into syscon would be your best option, I think. The console should indeed boot with broken HDMI barring something more serious having happened, a few of mine have a dead encoder chip and AV out is still good. If you do 'bringup' via syscon or (if i'm not mistaken) hold down the power button when booting until you get a second beep, if the console is actually booting, that should reset video and should get you AV out, assuming all else is OK.