Lenovo Y530 shuts off after few seconds

[piernov]

Re: Lenovo Y530 shuts off after few seconds

https://www.badcaps.net/forum/showpo...02&postcount=2

2.2. Don't suspect that something is shorted with no reason
Shorted components are not the only failure mode of a laptop. Additionally, some places will measure low resistance to ground under normal operation. In general, high power low voltage (<2V) power rails will measure less than a few hundred ohms to ground. CPU VCore will measure a few ohms only. GPU VCore with newer NVidia GPU can even measure less than 1 ohm. It's normal. If you suspect a short to ground, always report your exact resistance to ground measurements.

[unimatrix93]

Re: Lenovo Y530 shuts off after few seconds

https://www.badcaps.net/forum/showpo...02&postcount=2

Sorry for the late reply and thank you for pointing me to that post.

Here is some new findings:

Symptom:
- No power LED when plugging in charger.
- CMSRC is present 20V
- ACDRV is present 26.5V
- 3VALW and 5VALW is missing, however +3VLP and +3VALW_R is also present around the Lenovo IC. And 5V_LDO is also present at PU601.

What I found:
RV1114 has 20V on PIN1 but 16.8V on PIN2. Is this normal?
Also as I was measuring voltages on the middle of the PCB, I felt slight warm on my right hand as it was touching the area of the main charge IC (PU201 - BQ24780SRUYR). It feels like the IC or something around it is getting warm, not hot but definietly warm.

[mcplslg123]

Re: Lenovo Y530 shuts off after few seconds

On some newer boards, 3V/5V ALW will appear after switching. So check whether thay appear for the few seconds when you can turn on.

[unimatrix93]

Re: Lenovo Y530 shuts off after few seconds

On some newer boards, 3V/5V ALW will appear after switching. So check whether thay appear for the few seconds when you can turn on.

The schematic says its should be ON when AC is connected.

Also, I noticed the charge IC (BQ24780S) is getting slightly warm after plugging in AC, is this normal?