MacBook Pro A1286 no display

[mferna14]

Hi all, I am working on the MacBook Pro A1286 15" (Motherboard 82-2915-B). The problem was that it had a EFI password & the display was 100% ok. I removed the EFI Password by re-programming the BIOS Bin files. Soldered the chip back again, display was great & no EFI P/W. Thereafter I just did a PRAM reset, & then no display at all, just chime in the start & later I did a SMC reset, fans rans very fast & no chime at all. Now the condition is No Display. Why the the PRAM reset kill the system, cannot understand??? Does anyone know what wrong am I doing or any help would be appreciated. Thanks

[dellxps15]

Re: MacBook Pro A1286 no display

probably it had software repaired for bad gpu ?
remove r8911 and see if display comes in (white display)
99% it had efi password to prevent bios reset for that gpu software bypass.

[Stevedb]

Re: MacBook Pro A1286 no display

Did you backup your original bios? Put it back and see you have back display . If so modify your original bios with hxd editor and removed a pasw. Out youroriginal bios dump.

[piernov]

Re: MacBook Pro A1286 no display

Agreed with @dellxps15 , although without R8911 display should stay black if backlight enable&PWM aren't permanently tied to 3.3V (for backlight operation under High Sierra).
Dead GPU as always in this machine. Use one of the multiple hardware bypass methods (GMUX bypass with modded firmware, GMUX bypass with jumper wires, SPI ROM modchip…).

[mferna14]

Re: MacBook Pro A1286 no display

Thank you so very much for all chipping to my problem.. I will try all & let you guys know.

[mferna14]

Re: MacBook Pro A1286 no display

You were 100% right "dellxps15"., someone worked on it & the resistor R8911 is removed & surely they program the BIOS accordingly. I resoldered the same BIOS againwith the Password & 100% display., but now not getting nothing, no white screen or display. Can someone re-build the BIOS accordingly so that the laptop turns on again. The attachment is BIOS dump with the password in it. Thanks in Advance.