820-00840 / No boot / PP3V3_G3H Short to ground

Papaille

Member
And what about removing all capacitors on pp3v3_g3h rail? There is not so much on schematic… finding short with so less consumption may be little more difficult don’t you think? What’s the best way to investigate more by your opinion?
 

2informaticos

Administrator
Staff member
Best way is trying injection method as described.
If doesn't help, you can think to remove components one by one.
You can also heat the chips connected to 3v3_G3H; in case of accumulated crap causing leakage.

Doing nothing and just asking what else to do, doesn't help...
 

Papaille

Member
So,
I injected again on PP3V3_G3H.
On 3v board takes 0.16A, with 3,9V (the max i put on it), 0,23A

I use a thermal sensor, and find that U3100 is warming a little more than the rest (around 35°C while rest of the board is around 22°C). I'm sure it's in this area, especially around this component.

But with schematic, and the fact that with C3200/3100 and R3000/1 removed short was still there, i'm a little bit confused...

Actual PP3V3_G3H diode mode value is 0.133
 

Papaille

Member
I don't have a thermal imager, only a thermal sensor i can put directly on the board then read thermal value. Only area with a significant increment value is U3100 chip. All around seems to be only thermal diffusion from this point (U3200 is less hot than 3100).
I haven't tested other side of the board.
 

Papaille

Member
You're right. At the opposite of CD3215 components, heat is more present. Found what seems to be a burning point on a component witch doesn't exist on board schematic ! It's a PI(burn)USB32224BXEAE.
 

Attachments

2informaticos

Administrator
Staff member
That is the USB redriver chip; many times mentioned on the forum.
The board can work without it.
Maybe weird issues with USB devices connected may appear; you should replace it finally.
 

Papaille

Member
Right ! I've unsoldered it. Short is gone (around 0.413 in diode mode, more than 1000Kohms in ohms mode).

Waiting for a "new" U7000 and another PI3USB32 to test the board.

A little question : My hot air station go to 450° Celsius max (842 °F), and it was a little bit long and difficult to unsolder U7000 and this chip. Do you know the right temperature to remove properly and quickly chips on these types of motherboards ?

Thanks again for all the time you spend here.
 

2informaticos

Administrator
Staff member
Practise on scrap boards.
Also remove CPU heatsink.
Play with air flow, nozzle diameter and distance to board.
Each hot air station has its settings...
 

Papaille

Member
Hello 2informaticos,

So i received and replaced U7000. Plugged in and IT WORKS !!! 20v / 0,6 Amp at both USB-C ports !! so happy !

I received PI3USB32224BXEAE too (but firstly i just wanted to know if the board run fine without it)

So after that, i replaced PI3USB32224BXEAE and... stuck at 5,07 Volts / 0,00 amps on first USB-C port !!! (witch match with U3200 chip)
On the other port, board runs perfect (19,97 Volts / 0,58 Amps)

Removed PI3USB32224BXEAE to see if the prob is gone, but now board still stuck at 5V / 0 Amp on first USB-C port... so i resoldered another new PI3USB32224BXEAE, same thing ! (First Port stuck a 5V, other run fine)

Reading some values on both CD3215 chips (supposing are fine, worked well before adding PI3USB32224BXEAE)

PP3V3_UPC_XA_LDO : 0.609
PP1V8_UPC_XA_LDOA : 0.637
PP1V8_UPC_XA_LDOD : 0.584
PP1V1_UPC_XA_LDO_BMC : 0.614

PP3V3_UPC_XB_LDO : 0.617
PP1V8_UPC_XB_LDOA : 0.631
PP1V8_UPC_XB_LDOD : 0.581
PP1V1_UPC_XB_LDO_BMC : 0.609

With Charger connected on faulty USB-C port => PPDCIN_G3H_CHGR : 0,13V (same value for PPVIN_G3H_P3V3G3H)

Thanks a lot for your help !
 

Papaille

Member
Ok thanks.
It's really strange that the board works well on this port 2 days ago, juste before i solder PI3USB32224BXEAE, and now this port looks killed don't you think ?
A reflow on CD3215 is possible or it doesn't do nothing more ?

Taken voltages on U3200 to be sure :
PP3V3_UPC_XB_LDO : 3,31 volts
PP1V8_UPC_XB_LDOA : 1,81 Volts
PP1V8_UPC_XB_LDOD : 1,80 Volts
PP1V1_UPC_XB_LDO_BMC : 0,03 volts

Will see for a Q3200.
 

Papaille

Member
Thanks for your reply.
I made a mistake with board in computer, trying to see if everything was working fine (screen/battery etc)
Plugged on second port (linked to U3100) everything was fine (charging-aht-screen…). Unfortunately, i have unplugged from this port and replugged on the other port. USBc-meter show me 20v and 0 amp and all the machine shutdown, unable to turn it on again.
Checking ldo on U3200, missing smc one (open line). Everything stuck at 5v on each port, 0,3 amp on bottom, 0,144 amp on top. No pp3v3_g3h when plugged on usb linked to U3200, got it when plugged on u3100.
So I decided to remove u3200, and soldering another Cd3215c00 (from AliExpress)
with the first one soldered, missing all connections on the top left, like 1v8 ldo.
Replacing with the other I brought, all Ldo’s were fines, but missing some others lines. trying to plug on each port to see if it can communicate with the charger, got 5v17 on each port, 0 to 0.04 amp cycling on bottom and 0.00 amp on top.

will see for others supposed goods cd3215 chips, and resolder it. Reading that U3200 is the master, U3100 the salve. So without fully fonctionning U3200, board can’t turn on properly.

is there a special tips to not destroying this sensitives Chips when resoldering?
Thanks a lot again
 

Papaille

Member
Hello again !

So i received my "news" CD3215C00 chips. Soldering one of them on U3200 and....it's definitively alive 19,94V and more than 1 Amp on each ports !!!

Installing macosx, everthing works fine excepted a strange thing :

When i'm connecting my usb-c cable on first port (U3200 linked) it work on both side of the connector. When i plug this cable on the other port (U3100 linked) it work only on one side of the cable, returning the cable doesn't do anything (no charging, nothing detected)... Usb-c cables aren't supposed to be similar on each side? how can it be possible?
 
Top