Lenovo ideapad 5 windows 11 update disable charging circuit?

[bogart219]

Hello.Still working on this problem little by little each day, reading and studying. The main thing I'm trying to accomplish now is following the 5 volts from the usb-c jack and see where it stops.

Can you identify what kind of diode this is?


I believe the diodes in this picture are are back to back avalanche diodes in one package. What is the purpose of this setup? I'm assuming one of these is the usb-c protection chip (if this board has one that is).


Thanks!

[bogart219]

Hello.Still working on this problem little by little each day, reading and studying. The main thing I'm trying to accomplish now is following the 5 volts from the usb-c jack and see where it stops.

Can you identify what kind of diode this is?


I believe the diodes in this picture are are back to back avalanche diodes in one package. What is the purpose of this setup? I'm assuming one of these is the usb-c protection chip (if this board has one that is).


Thanks!

Nevermind. I found out these are TVS or ESD diodes. thanks.

[bogart219]

Hello fellows, I'm still plugging away and haven't given up yet. Here is something that doesn't seem right to me. This a power supply which I believe is for the ram at 1.2 volts. With my meter in the diode mode (beep), I get steady beeping across the one mosfet, the inductor and three capacitors, all are circled in this pic. am I barking up the wrong tree? Thanks!

[bogart219]

Does this description of low & high side mosfets sound correct? I'm having a hard time wrapping my head around this when he says "goes to ground". Wouldn't that be a dead short?

[bogart219]

Hello friends, still plugging away on this motherboard. I don't work on it every day but after reading or watching something on utube (which I do every day), in trying to gain knowledge. I was looking for shorts in this area of the motherboard ;


I kept reading a dead short on that inductor PL3001, along with some other caps and a mosfet. The only thing I could think of doing at this point was voltage injection. I was aware of the area I was in, which I believe was for the ram, so I kept my test voltage at 1 volt and set my current at 2 amps. ( I was using a HR1520 short killer). I applied the voltage at the PL3001 inductor. I checked all over both sides of the board but didn't see any hot spots. (all the while the short killer is beeping), until I noticed the CPU getting hot. With one volt I shouldn't have turned anything on I wouldn't think. The only conclusion now is that I now have a shorted CPU which means game over.

What do you guys think? Once more thanks!