Lenovo Y530 power(?) issues

unimatrix93

Member (✔)
Hello everyone!

I got a faulty Lenovo Legion 5 Y530-15ICH (MB: NM-B701 rev1) under my hands and I simply cannot troubleshoot the cause of the problem.

The symptoms:
The notebook only turns on If I leave it turned off (With only the battery and cmos bat. plugged in) for a while (1h+). And I it does turn on and succesfully boots to windows, it does work for a while until it looses power (notebook shuts off completly) or I turn off by clicking shut down in Windows.

If I turn it off I have to wait again until it can start up again. Otherwise the pwr comes up for a few seconds, without display (altough sometimes I see the Legion logo apper without backlight.) and it turns itself off.

What I measured:
  • I tested the charger, charger port, battery, the 5V,3V if they are present. Everything present.
  • I also measured UE1 controller chips (IT18226E) 77,3,21,83,85,128,108,76,90,97,123,110,111 pins too, If anything missing but looks fine to me.
-Also, I checked on the BIOS chip if it getting voltage, because I had quite a few times when the system crashed and turned off when I entered the BIOS/Novo menu.
- The C55 capacitor next to the USB (EAY28 6.3V) won't drain power even if the batt/AC disconnected. I tried to discarge it by holding the pwr button for 30 sec but nothing happens. It's still measures between 0.20-0.30V and slowly depleting.


Things I found:
- As I mentioned above, If I leave it off for a while it will most likely start up normally until the next crash/restart. Plugging in the AC charger seems to stopping this to work however.

- The other thing is If I connect the AC charger while the CMOS battery in plugged in, the PWR button LED will flash for 1s. But If I unplug the charger and reinsert it it will not flash whatsoever UNTIL I unplug the CMOS battery. The PWR LED flashes every time If the CMOS battery is not connected.

It's seems like something causing a shortage maybe and It's stays this way until the problematic component discharges completely or something. I'm just making theories.

I hope I provided enough info and thank you very much for your help in advantage!
smile.gif
 

Admin

desktops & Laptops
Support
I cannot see any water oxidation on it with naked eye, but I will give it a shot!
and do not forget to change the thermal paste for the cpu and gpu .
 

unimatrix93

Member (✔)
While I waiting for the stuff to arrive, I found out that If the CMOS battery is not plugged in, the CPU doesn't produce any heat, but if the CMOS battey is present the CPU gets blazing hot to the touch after pressing the power button.
 

Admin

desktops & Laptops
Support
While I waiting for the stuff to arrive, I found out that If the CMOS battery is not plugged in, the CPU doesn't produce any heat, but if the CMOS battey is present the CPU gets blazing hot to the touch after pressing the power button.
Cpu goes hot on every motherboard it way they use fan and thermal paste.
 

unimatrix93

Member (✔)
Hello again,

So I cleaned the motherboard with isopropyl alcohol and it made no change sadly. :(

Anything else I could try? Or should measure?
 

unimatrix93

Member (✔)
i don't know but what i can tell you is this mosfet need what we call a driver voltage without this one it will not open .
Thanks for the answer.

I looked up on this IC Power chip which gets the 27V.

It's a Texas Instrument BQ24780SRUYR SMBus 1-4 cell Buck battery charge controller.


As you can see the document mentions an operating Voltage between 0 and 36V for the ACDRV line, but we I still don't know If this 27V is normal on the VIN line.

The motherboard's schematic does not specify this voltage anywhere as far as I can see.

Schematic:
 

Admin

desktops & Laptops
Support
Thanks for the answer.

I looked up on this IC Power chip which gets the 27V.

It's a Texas Instrument BQ24780SRUYR SMBus 1-4 cell Buck battery charge controller.


As you can see the document mentions an operating Voltage between 0 and 36V for the ACDRV line, but we I still don't know If this 27V is normal on the VIN line.

The motherboard's schematic does not specify this voltage anywhere as far as I can see.

Schematic:
It's normal you may need to change your old mosfet .
 

unimatrix93

Member (✔)
Hello again and happy new year!

After a very long wait, I finally received the MOSFETS and I replaced them, but sadly the problem is still persist and the 27V is still there. :(
 

Admin

desktops & Laptops
Support
Hello again and happy new year!

After a very long wait, I finally received the MOSFETS and I replaced them, but sadly the problem is still persist and the 27V is still there. :(
ACDRV 27v is normal .
 

Admin

desktops & Laptops
Support
try to work on the motherboard without lcd screen and without battery .
and if sometime you can see the logo without backlight that mean the Line of 19V is not good maybe some caps or bad mosfet .
 
Top Bottom