820-01041 stuck on 5volt 220mah

[dellxps15]

hi all, got this board not powering on. it has 4 usb-c port and at start i got this situation:

1 usb of each side was on 5 volt and 120mah drain, and 1 usb of each side had 5 volt and 480mah.

after replacing 2 usb of same side cd3215C00 (should be ok) i had 5 volt and 120mah on all port, but on other side of replaced cd3215 i had one port not worning if cable was inserted one way ( work just opposite side cable)

after another inspection i see one usb not giving PP3V3_UPC_XB_LDO and usb-c getting hot, so replaced the other 2 usbc and finally now i have all usb stuck 5 volt 220mah.

PP3V3_UPC_XB_LDO is present on all 4 cd3215.
PP1V8_UPC_XB_LDOA is present.
PP1V8_UPC_XB_LDOD present
pp3v3_g3h_rtc present
PP1V1_UPC_XB_LDO_BMC Missing

ppbus _g3h is 12,3 volt

on usb-c rom u2890 i have 3,3 volt on pin 3,7,8. on pin 1-2 i have volt on pin 1 and 0v pin 2 resistor (r2892 r2893 ) both 3,3k

on usb-c rom ub090 i have 3,3 volt on pin 1-3, 5-8.

any tips on where to look at since usb-c mac with 4 port are a pain to diagnose.

did sone 2 port mac and usb c cd3215 come back to working condition just after replacing them.

[mon2]

Re: 820-01041 stuck on 5volt 220mah

PP1V1_UPC_XB_LDO_BMC will be active if using this port to power the laptop. Check it.

[dellxps15]

Re: 820-01041 stuck on 5volt 220mah

i checked that volt on all 4 chip but never came , using original apple psu.
do u think problem is rom , isl or bad cd3215 ?

[mon2]

Re: 820-01041 stuck on 5volt 220mah

Remove all power. Meter in DIODE mode.

Red meter probe, yes Red, to ground.

Black meter probe to point to test.

Measure the DIODE mode reading of each LDO rail of each CD3215. Post each measurement.

Example readings:

Good board (diode mode):
PP1V8_UPC_XA_LDOD=0.483V
PP3V3_UPC_XA_LDO=0.515V
PP1V8_UPC_XA_LDOA=0.525V
PP1V1_UPC_XA_LDO_BMC=0.520V
PP1V8_UPC_XB_LDOD=0.484V
PP3V3_UPC_XB_LDO=0.515V
PP1V8_UPC_XB_LDOA=0.525V
PP1V1_UPC_XB_LDO_BMC=0.520V

Update:

Is the psu the recommended power adapter for this unit?

Can you test the power adapter with another type C device? Does the adapter cycle to other power delivery contracts or stuck at 5 volts?

[dellxps15]

Re: 820-01041 stuck on 5volt 220mah

on steam deck it goes to 15 volt.
later ill check giode value of each cd3215.

tnx for reply

[dellxps15]

Re: 820-01041 stuck on 5volt 220mah

measured these days value... all reading almost ok.. someone read 0.485, others 0.570.

same as before.. all voltage present except 1.1 .

i'll try doing a dfu when i get keyboard.

[Simplebeans]

Re: 820-01041 stuck on 5volt 220mah

i checked that volt on all 4 chip but never came , using original apple psu.
do u think problem is rom , isl or bad cd3215 ?

Your not getting PP1V1_UPC_XB_LDO_BMC on all 4 CD3215's? Did you check the grounding capacitors on all 4 lines?