820-02020-A Stuck 5V

Hello
I have this clean board stuck on 5V

-USBC1 takes 0.165A
-USBC2 takes 0.145A

Not sure how to start with this M1.

What is the equivalent to PP3V3_G3H?

PP3V8_AON: 0V
 
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Replaced U5700 and the board takes now 20V 0.200A when connected to UF500.

When connected to UF400 only 5V and the USB-C meter restarts.

Any idea? Thanks!
 
I measured the power sections, I coulndt find any clue.

UF400
PP5V_S2
PPHV_INT0_AONSW 0.543
PPVBUS_USBC0 0.139
PP3V3_S2_UPC
PP1V25_S2
PP3V3_UPC0_LDO 0.487
PP1V8_S2
USBC0_3V3LDO_EN 0.525
UPC0_SS 0.561
PP1V5_UPC0_LDO_CORE 0.504

UF500
PP5V_S2
PPHV_INT1_AONSW 0.543
PPVBUS_USBC1 0.142
PP3V3_S2_UPC
PP1V25 S2
PP3V3_UPC1_LDO 0.494
PP1V8_S2
USBC1_3V3LDO_EN 0.529
UPC1_SS 0.561
PP1V5_UPC1_LDO_CORE 0.505
 

2informaticos

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Do you get same voltages on UF400/500 chips?

The logic part of UF400 is OK, as it boots first (from TBT ROM).
UF500 boots from UART lines connected to UF400.
Check and compare diode mode readings between CC1/2 lines.
Also check all resistors from pages 57 & 58.
On page 59, compare diode mode between USB-C lines.
 
Couldnt find any different measurement on the chips.

I replaced UF400 and the machine taking 20V y both ports.

Now, when connecting the screen I only get 5V on both ports. If I disconnect the screen I can hear it chimes.
I took out the board again and on the bench i do get external video

Any help?
 
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I have PP5V_SW_LCD shorted to ground when connecting the screen (0 ohms)

When screen disconnected I got 58ohms to ground or 0.064V (diode mode)

-Any recommendation on the screen?

-The 0.064V sounds good?
 
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