Search results

15-25% of issues is a lot! You have just motivated me to learn more about BIOS flashing. Do you recommend any tutorial on this, or a tutorial on ME region cleaning?

I heated the MCP, now I get no video and no backlight (and still no sound, even without RAM). I checked all the rails, they are still ok Fan spins, no red light on mouse, just the peak when starting PPVCORE_S0_CPU=0.99V LVDS_IG_PANEL_PWR=0V State should be S0: SMC_PM_G2_EN=3.4V PM_SLP_S4_L=3.32V...

R7403 and R7402 were ok. I swapped the BIOS chip with another I know was ok, and the board started normally, blinking folder! Thanks again Well noted also, PPVCORE_S0_CPU is 1.12V with the wrong chip (not booting), 0.80V with the good chip and booted I am curious to know: can you tell which...

Hello, Here are the symptoms: - green light on charger ok, current around 0.7A - fan spins ok - no chime, no long beep even if no memory - pulse of red light on mouse when starting, then nothing - nothing on display Measures: ALL_SYS_PWRGD=3.32V PPBUS_G3H=12.6V PP3V42_G3H=3.48V PP3V3_S5=3.33V...

No luck for this one, still no sound. Either the chip was also bad, or I fucked it, or there is another issue that I don't see at all. I also checked that there is no short on SPKRAMP_SHDN on the amps, I measure 75kohm, seems ok. So, for this one I give up :(

In fact it is strange, because Apple put the "_L" for HDA_RST_L (tagged RESET* inside the chip), not on SPKRAMP_SHDN Anyway, this HDA_RST_L is 3.3V. So chip is enabled, power rails ok, no corrosion: tomorrow I will try to replace my first 48 pin chip...

I don't agree. For example the datasheet of U6610, LM48556TL, says for SPKRAMP_SHDN (pin SD*, number C3): "Active Low Reset Input. Connect to VDD for normal operation. Drive SD low to disable." So I expect 3.3V to avoid shutdown, no? I don't find any corrosion. So, I change the CODEC, U6201?

Hello all, This board works but it has no audio, not even the chime at start up. Prohibitory sign is displayed when trying to change the audio level. No beep sound also if no memory installed. In system preferences > sound: there is nothing for output or input. If I plug a audio USB adapter...

Unfortunately for this one I have no BIOS chip to swap and try, so it may finish as a donor board... Or I buy one faulty on Aliexpress for 15?? Any experience about this provider for spare parts?

It works!!! Swaped the BIOS chip, and here is the blinking folder!! Wooow... Thanks for the idea!!! Now I have 2 good boards and one chip :D About cleaning ME region: no idea about that, is it mandatory in case of new BIOS chip? If the board passes AHT, would that be ok? Otherwise I made some...

Thanks, I just want to go as far as I can, especially because I do not risk a lot with this board. BIOS: this correspond to the "Boot ROM version", in the Hardware overview? Is this contained in the EFI chip? If yes I can replace the EFI chip with a good one from the exact same board reference...

Hello, On the list of S5 rails, the schematic says 1.05V for PP0V9_S5. So we should trust the value inside the name, not the one in the schematic? Resistance to ground at 3V42_G3H: starts at 20Mohm, decreases, then stabilizes after several seconds at 223kohm

Thanks! Caps lock is faint green from the moment it chimes. It never disappears, stays always with the same intensity, pressed or not. If I press caps lock (or ESC, or space bar) several times just after the mouse switches off (the 30s), red light appears for 3-4 seconds, then no reactions. If I...

Hello all, - Green light on charger OK, I=0.65A with U=18.5V - Fan spins OK - No chime, no backlight - Mouse in USB: pulse of red light when starting, then off All rails are ok Measuring - I put () for the theoretical values on the schematic: S0 rails: PPVCORE_S0_CPU (1.25V):0.99 PP1V05_S0...

Hello all, This is my first post! Don't hesitate to tell me where I can improve. So, I have a board A1286 mid 2012, 820-3330, with no video - Green light on charger OK, I=1.85A with U=18.5V - Fan spins OK - Chime OK - Backlight OK - Grey screen also on external screen, but no image - Mouse in...