HP 2000 - 14Volt instead of 3.3 volt

[IamPritesh]

Hi friends,
Hope everyone is safe and healthy. I have this HP 2000 series laptop which has no display. Upon checking I found that 3.3 always volt id not generated , instead it generates 14 volt. I have replaced the upper mosfet but still the same. There is no/negligible gate voltage of the mosfet.
5 volt is generated fine though.

Is the step down IC faulty ? Please advise

MB PART NO : 010170100-600-G

[Duranitron]

Re: HP 2000 - 14Volt instead of 3.3 volt

do you have the schematics of this hp 2000

[SMDFlea]

Re: HP 2000 - 14Volt instead of 3.3 volt

The schematic is already posted - https://www.badcaps.net/forum/showth...10170100-600-G

[Duranitron]

Re: HP 2000 - 14Volt instead of 3.3 volt

schematics doesnt match...

[IamPritesh]

Re: HP 2000 - 14Volt instead of 3.3 volt

schematics doesnt match...

Yeah it doesnt match .. Any further assistance on I have 14 volt instead of 3.3 always ..

[IamPritesh]

Re: HP 2000 - 14Volt instead of 3.3 volt

Can anyone guess what could be the reason ..

[mcplslg123]

Re: HP 2000 - 14Volt instead of 3.3 volt

Measure it on the other side of the coil or cap connected to 3v coil.

[IamPritesh]

Re: HP 2000 - 14Volt instead of 3.3 volt

Measure it on the other side of the coil or cap connected to 3v coil.

If i remove the upper mosfet connected to the 3V line, i notice that there is no voltage even on the 5volt line.

I would also like to mention that if i trigger the board, it the led glows, the fan spins and the cpu also gets heated. However there is no display and obviously there is 14 volt on the coil of 3.3 volt line.

[piernov]

Re: HP 2000 - 14Volt instead of 3.3 volt

I really doubt there is actually 14V on the 3.3V rail. That would kill whatever that's on it and the computer wouldn't turn on. Make sure you are measuring after the inductor. Cheap multimeters will display random numbers when measuring before it, where the voltage is switching at high frequencies.

[mcplslg123]

Re: HP 2000 - 14Volt instead of 3.3 volt

I agree with piernov's views and thats why i suggested to measure on the other side of the coil or the cap connected to 3v coil. You have not answered that. If you really get 14v on coil which is supposed to be 3v, mb will get fried the moment it is turned on. So do check again.