820-00875-01 no power

iClub

Member
Hello my friend, I don't have this electrical scheme, but I imagine it looks or feels like 820-00840, I used it as a reference. No signs of oxidation, no image, cooler turns sometimes and the external ssd turns on the led.


voltage:
PPbus_g3h 13.0v; PP3v42_g3h; PP3v3_g3h 3.41V; PPDCIN_G3H 20.2v; PP20V_USBC_XA_VBUS_F 20.2; ALL_SYS_PWRGD 3.21V; PP3V3_G3H_UPC_XB 3.31V; PP1V8_UPC_XA_LDOD 1.8V; PP5v_s0 5.11V.
 

2informaticos

Administrator
Staff member
PPBUS_G3H looks correct and you get even S0 volatges; why wasting time measuring USB-C area then?

So your board powers on, but doesn't work; there is a difference, don't get confused.

Check L7210/20 voltage.
Did you check for USB activity?

 

iClub

Member
voltage:
CPUVR_SW1/PPVCCCPU_S0G_PH1 0.98V; PP3V_S0 3.31V; PP1v8_S0 1.81V; PM_SLP_S0_L 3.32V; P5VS0SW_CT2 9.95V.

Mac recognizes the external SSD, but the system that is on the ssd does not start. No image on external HDMI.
 

iClub

Member
Estou com dois mac como este, sem imagem, apenas o cooler gira e para. 820-00875 e 820-00840.
 

iClub

Member
I put this BIOS that you gave me and it still has the same defect. The plate has no signs of oxidation, the voltages are okay, I don't know where the problem may be, have you caught any cases like that?
 

iClub

Member
u3100 when changing the USB-C port it does not have heating in the thermal camera, only the u3200.
 

2informaticos

Administrator
Staff member
You said USB adapter has light on.
Is that Link LED, or just power LED?
A normal USB adapter for SSD/HDD should have 2 LEDs...
 

2informaticos

Administrator
Staff member
I cannot find U7330 in schematic.
Do you mean u7370 instead?

Do you get correct voltage at L7370?
The board will not work without that voltage...
 
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