Hi Guys,
I need your help to check my BIOS, it stuck on 3/4 progress apple logo loading bar.
Thanks
I need your help to check my BIOS, it stuck on 3/4 progress apple logo loading bar.
Thanks
Attached Files
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Hello everyone,
Some time ago I acquired an imac computer model A1311 that does not boot (motherboard ref. 820-2494-A).
The power supply is working properly (I have two), it delivers the 12V on pin 4 of the power connector (PP12V_S5).
As I have the schematic diagram and the boardview, I have made a series of measurements, obtaining the following results:
PP12V_S5 -> 12V
3V3REG_VCC -> 3.12V (something low?)
PP5V_S5_LDO -> 0.02V
3V3REG_VCC -> 0.0066V
I have also measured the resistance to ground on the coils, and I can't find... -
Main board : 820-3126-A
Power : OT8043-290H R03BE9-0008I- apple P/N: 614-0444
EMC 2428
Problema , alla pressione del tasto power(S5010) tutto spento , led 501acceso .
Sui pin dell'alimentatore sono presenti :
Pin 6 4v6
Pin2 12v
Sul pulsante power sono presenti 3v3 , che alla pressione si genera il segnale SMC_ONOFF_L , il quale va al pin 104 di U4900 = H8S2117 LFBGA
ho difficoltà nel capire quale sequenza , quando arriva il segnale SMC_ONOFF_L, deve
eseguire U4900 per attivare l'alimentatore
... -
Hello guys, I need to remove password from this bios dump. Thanks in advance...
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Apple MacBook Pro and iMac Schematic & Board Vie
A2991 2023 820-02935 16 M3
A2780 2023 820-02652 16 M2
A2439 2021 820-02009 iMac 24... -
Hello. Got an iMac after a power surge. The PSU survived, but the motherboard did not. Symptoms - after connecting the power, one LED (the rightmost one) lights up, 3.28-3.3v hangs on all legs of the bios flash drive, except for 4. The PCH is heated, low resistance PP3V3_S5 - 30 ohms, PP1V05_S0_PCH - 10-15 ohms. Powered through laboratory power supply 3V 1A to PP3V3_S5, the hub heats up wildly. USB data lines have the same resistance, not underestimated. There is no response to the power button.
PP12V_S0 - 0.05V (should be 0), PP1V05_S0_PCH - 0.5V (should be 0)
I've checked...10-22-2022, 04:10 AM