820-00923 20v 0.0A No PPBUS

[JdYoda]

Hello everyone

Board came by liquid damaged and messed up by previous service. Some components are missing, dirty, CD3215 overheated etc. No voltage on USB-C meter at all

What is done for now:
Replaced all 4 CD3215
Replaced U7000
Soldered back missing U8000 and U7960
Soldered back missing Q7040 and Q7030

Now got back 20 volts, but 0 amps
PPDCIN_G3H 20 volts, stable
PPBUS_G3H 0.6-0.9 volts. No short
R7020 is ok, 0 ohm, 20 volts
R7021, R7022, R7061 and R7062 is 1 Ohm as it should be
U7000, Q7030 and 7040 as i said is already changed

Is it something else can pull the line to the groung, or u7000 still doesn't work properly by some reason?

 

[2informaticos]

Diode mode to ground at PPBUS_G3H?

Post U7000 voltages; P_IN, AUX_DET, VDDA/P, AUX_OK, A/BMON.
Be sure R/C7030/40 all good.

 

[JdYoda]

Diod mode for PPBUS - 0.42

u7000:
P_in - 20.0 v
Aux_det 6.6 v ( is it a normal value?)
Vdda/p - 5.0 v
Aux_ok - 3.4 v
Amon - 0 (diode mode 0.64)
Bmon - 0 (diode mode 0.64)

All elements around U7000 are good. No short/values equals the schematic

 

[2informaticos]

You should change U7000.

Do not expect miracles from this board, of liquid damaged and already messed up by someone else.

 

[JdYoda]

Yes, you right about miracles. But i just want to understand why ppbus is missing. Just collecting knolege and expirience piece by piese to my head

Changed U7000 one more time, AMON and BMON is still 0 volts. Other values also didn't changed
Is there something else i can pay attention to, or this board is just a waisting of time?

 

[2informaticos]

Very likely wasting time.
U7000 expect SMC communication, to generate PPBUS_G3H.
Some blocks of SMC work, as you get 20V on charger.
This do not assure SMC is in perfect working condition.

 

[JdYoda]

Ok, thanks anyway for an answer