Liquid damage, new logic board, fans spin no chime no screen

Hi guys, feeling defeated as of now.

I spilled a large coffee, turned everything off and let dry for days as one should.

Tried it, nothing. No orange charging light.

Replaced logic board and it showed the orange light. The fans suddenly started to spin at full speed but no chime and no screen.

Tried turning on with the power on button but nothing. I suspected it was the keyboard so I disconnected the charger and the keyboard and back light ribbon, then used a flat headed screwdriver on the powerpads to fake a power on button press. This started the machine, the fans on full speed, the ssd lights on, yet still no chime and no screen.

I've inspected the screen connector as well as everything else and can't see any corrosion or any abnormalities.

So my understanding is the logic board is OK, the battery is OK, ssd OK, maybe the keyboard is dead but the powerpad turns it on but no chime and no screen.

What do I do next? Other than to smash it to pieces, what's next?

Thanks so much in advance!

Hi Dan, thanks for your speedy reply.

I took it to a repair shop the guy said it’s probably the logic board and quoted me something silly so I bought a replacement logic board online that said was tested and that had a 30 day return.

The new logic board fixes the charging light issue. The new logic board powers the fans when I plug in the charger both with the battery in and out, as well as spins the fans when only operating under battery and switched on using the power pad.

I've disconnected the screen cable and the battery and when I charge it the fan spins and the harddrive lights up. I've also tried this with and without the ssd and Bluetooth card with no luck.

The new logic board is from the same year (mid 2012) model number a1466 2ghz i7 8gb ram, same as what it was replacing.

I've also tried with and without the speaker and webcam cables and booting with just the charger and no battery, still no chime (I know there won't be a chime if there's no speaker connected) but still no screen.

With the keyboard ribbon and the back light ribbon connected I'm still able to use the power pad to fake a power button press which suggests the keyboard connection isn't being registered.

I'm now thinking perhaps it's as simple as a smc or pram reset but without the keyboard functionality I'm able to press and hold the required buttons.

Should I buy a new upper case, with the track pad and keyboard with backlight and attempt the smc and pram or disk utility?