AC adapter power is sucked from 19.9v to 0v?

[Irfan-1]

Hiya my HP OMEN 15-DH1005NA not working so i opened it to check the voltage, when i check the ac adapter power i see 19.9v which looks fine but when i connect the battery to the motherboard the ac adapter power starts to lower down from 19.9v to all the way to 0v,

to get the ac adapter power back to 19.9v i need to unplug it for a few seconds and plug it back so it will work as 19.9v again
anyone has any idea why this happens???

[swerl345]

Your issue suggests a short circuit or faulty battery/motherboard component. Try using a different AC adapter to rule out adapter failure. Test powering the laptop without the battery if it works, the battery may be faulty. Also, inspect the motherboard for damaged capacitors or MOSFETs. If the problem persists, a board-level repair may be necessary.

If this solution does not work, let me know I will explain with example.

[Irfan-1]

Hiya thanks for your reply, which capacitors or mosfets will i need to test?

[Irfan-1]

Ac adapter and battery is fine, there might be a problem with component abd mosfet, but i don't need which mosfet to check first?