820-00840-a - 5.20v

[menatwork]

No liquid Damage and just stopped working.

Here is some measurement:

PPDCIM = 5.20V Drops to 4.7V (LOOP)
TBA_AUX_DET = 1.3V (normal is 5V)
PP3V3_G3H = Loop 3.4V and 3.2V after 2sec
BUF_SMC_RESET_L =3.4V and 3.2V after 2sec
SMC_BC_ACOK = 3.4V


Diode Mode

L7030 = 0.449
L6995 = 0.373
F7000 - 0.412


Any hint from here?

Thank you!

 

[2informaticos]

"(normal is 5V)"
Yeah, when you get 20V at R7020.
1.3V is actually correct; calculate resistor divider.

You get 5V at both USB-C connectors, connected in both directions (4 tests)?
Check diode mode to ground on all power rails of CD3215 chips.

Inspect redriver chip for any small hole on top of it...
https://boards.rossmanngroup.com/search?q=redriver&searchJSON={"keywords":"redriver"}

 

[menatwork]

TBA_AUX_DET = 1.3V (normal is 5V) that what a mean - Normal.

 

[menatwork]

You get 5V at both USB-C connectors, connected in both directions (4 tests) Yes.

Diode Mode:

U3100
C3100 - 0.380
C3101 - 0.195
C3104 - 0.529
C3105 - 0.499
C3106 - 0.537
C3108 - 0.524

U3200
C3200 - 0.380
C3201 - 0.195
C3204 - 0.523
C3205 - 0.495
C3206 - 0.533
C3208 - 0.528

4) Inspect redriver chip for any small hole on top of it - Looks Great!

 

[menatwork]

I'm sorry, but what you mean about "USB ROM chip signal"?

U2890
Pins:1-2-3-5-7-8 = 3.3V
Pin 6 - 0.23V

 

[2informaticos]

You should check with o-scope.
U2800 and U3200 are both connected there.
If no activity detected, something still wrong with USB-C area...

 

[menatwork]

What about Pin 6 - 0.23V ?

 

[2informaticos]

I don't see external pull-up resistor on it, so must check on o-scope...

 

[menatwork]

I replaced U3200 and everything works.

Thank you for the hints.