HP Pavilion x360 14m-dh0000 no power

[Tend0]

Hi everyone I need our help to find the faulty components in this motherboard FAROE_DIS_X32_MB_MV 18742-1 the MOSFET PQ4303 was short to ground and I replaced it and I Short again I want to inject voltage but I know if it's good idea

[mon2]

Re: HP Pavilion x360 14m-dh0000 no power

Hi. Can you link or post the schematic for this logic board if on this forum?

What is the part # for the original PQ4303 ?

Which replacement was used ?

Remove all power, meter in resistance mode.

What is the resistance to ground of the source pin? Gate pin? Drain pin for this mosfet?

[Tend0]

Re: HP Pavilion x360 14m-dh0000 no power

Original PQ4304:SM4378 30v,49a
Replacement used:PK616BA 30v,50a
Résistance : source drain:0,8
Source gate:OL

LINK to schematic --> https://www.badcaps.net/forum/troubl..._mb_mv-18742-1

[mcplslg123]

Re: HP Pavilion x360 14m-dh0000 no power

I think the mosfet in question is PU4301 and not PQ4303 or PQ4304. Is this correct??

What is the resistance on Source and Drain pins on PCB(PU4301 removed)??

[Tend0]

Re: HP Pavilion x360 14m-dh0000 no power

Sorry guys it's PU4301
No resistance on remove MOSFET value
Yes sir PU4301 is remove

[mcplslg123]

Re: HP Pavilion x360 14m-dh0000 no power

How you are measuring resistance?? Put your meter to 200K scale,then put black probe of DMM to ground and red probe on Source/Drain pads of removed mosfet. There has to be a reading?? If meter show OL then move on to higher scale on DMM.

[Tend0]

Re: HP Pavilion x360 14m-dh0000 no power

I use unit-ut890c I measuring automatic mode

[Tend0]

Re: HP Pavilion x360 14m-dh0000 no power

Hi everyone thanks for us �� the issue was resolved I read beginning topic and inject 1v and 1,5amp successfully at 2 and I find heating ceremaic condensator I removed it and replaced another and replaced also the burn MOSFET by MDU 1516 and pc start very well but MDU 1516 get hot

[samz2021]

Re: HP Pavilion x360 14m-dh0000 no power

hello all i have the same problem mosfet sm4378 is burn please equivalnet

[mon2]

Re: HP Pavilion x360 14m-dh0000 no power

Do you have donor boards available? Look for the charger IC on other laptop boards. If the charger IC is the BQ series then they will also use the same N-channel mosfets.

Be sure to review the original pinout and where is the pin #1 dot on the body. Replace the defective mosfet.

Lots of flux + heat + enough air pressure to remove and solder the part. Protect the tiny parts nearby with kapton tape.