A2337 5v 0.06a-0.45a no power

[sauce]

Hi,

I am trying to repair this A2337.

My USB-C meter stuck at 5v but make some peaks.

All main voltages fluctuate.

PPUS_AON 11v to 12.25v and so on.

I removed F5200 and PPBUS_AON is stable 12.25v

So I tried to come with my power supply on PPBUS_AON pad (still without F5200 but with USB-C meter plugged in) and I can see my USB-C meter go to 20V but rebooting.

I also tried to put F5200 back and come with my power supply to battery connector and my USB-C meter go to 20v but still rebooting (but CPU gets hot !)

Do you have any ideas what to check ?

With my thermal camera I can see pulses on L8230 and also U8100 near a corner on the same side.

I checked all capacitors/coils but no shorts at all !

Thanks in advance.

[mon2]

Test the voltages on the ssd rails.

[sauce]

Hi,

All voltages are fluctuating on SSD rails.

The only voltages that are stable are from UBC-C :

PP1V5_UPC0_LDO_CORE 1.582V
PP3V3_UPC0_LDO 3.4V
5V on fuses

PP3V3_S2_UPC is fluctuating

[mon2]

Remove all power. Measure the resistance to ground of the rails that are not stable.

[sauce]

ok I try that do you have a list of values somewhere ?

[mon2]

I do not but in general, if the voltge at the output of the regulator is low, it may be due to a lower than normal resistance on this load = SSDx. Remove all power and measure the resistance to ground. What is the measurement?

Also, is the enable pin for this power rail also pulsing?

[sauce]

Hi,

I think i will stop because i found a knocked off component so this card has been touched by someone else.

Thank you for your time.