820-00923 no video

[macfixer]

Hello,

Got a liquid damaged macbook, "boots" aka it draws normal current with and without battery. Without it draws around 0.8A 20V, with battery its up to 50W
No display output on internal, if i disconnect internal and test external i dont get video either. (verified external of course)

Inspected board on both sides, nothing is critically damaged, only a few oxidized caps etc.

Fans spin, cpu gets hot

Board has been handled by an unknown tech before be, antenna-cable metal loop for screw was under the board and a clasp is missing

Dont have too much experience diagnosing no video.

Thanks

 

[2informaticos]

Do you get USB activity (not only power)?
Post CPU core voltage after 15 seconds.

 

[macfixer]

No USB activity
1.059V on PPVCC_S0C_PU after 1 minute

 

[2informaticos]

Then the board is stuck, doesn't really boot.
CPU core should drop to 0.6V aprox.

Is probably waste of time, if board was messed up before.
Can't discard knocked off components, or broken traces.

You can try new BIOS, just in case.

 

[macfixer]

Interesting, might try new BIOS then, thanks for the help