HP Pavilion 17-ab091ms - white charging light, but no power

[BMCappelletti]

Re: HP Pavilion 17-ab091ms - white charging light, but no power

The mosfet appears to be turning ON since the gate is lower than the threshold value to allow for the source & drain to conduct.

See attached.

Remove all power.

Meter in resistance mode.

Place one meter lead on the pins 1-2-3 of the same mosfet.

Probe with the other meter lead near the IC (I think the one near the large coil) till you here a meter beep.

Found nothing on that IC.

We are looking for the IC that is linked to this mosfet. That is, the ~20v enters the board and then through the thick traces mates with a switching regulator. Believe it is the one near the large coil. Wish to be sure it reaches the regulator.

Then the local coil is used to reduce the DCIN voltage to some other value.

After the above resistance check, configure your meter to DC Volts (20V or higher).


What is the voltage at the coil (with reference to ground) when the DC adapter is attached ?

No reading. 0V on the multimeter.

We are confirming that the DC adapter voltage is reaching the first regulator and that the first regulator is performing its duty to turn on and produce some voltage rail.

[mon2]

Re: HP Pavilion 17-ab091ms - white charging light, but no power

There are no markings on the IC near the coil ? From the picture, there appears to be something faint on the top surface.

Try applying some alcohol with a Q-tip that may enhance the text under the right angle of light. There must be some markings on the component - unless the part is burnt out and caused the text to be distorted.

Since we have no schematics, we can only work with the part values with hope to decipher the workings of the power supply. From tracing the PCB, it appears that the power rail is connected to the IC with the missing markings.

[BMCappelletti]

Re: HP Pavilion 17-ab091ms - white charging light, but no power

Sorry, it says MS6HH.

[BMCappelletti]

Re: HP Pavilion 17-ab091ms - white charging light, but no power

The one next to the other large coil, above that one, says Z2281QIK.

[mcplslg123]

Re: HP Pavilion 17-ab091ms - white charging light, but no power

Sorry, it says MS6HH.

Its most liley a 3v PWM IC.(Sylergy code -MS)

[mcplslg123]

Re: HP Pavilion 17-ab091ms - white charging light, but no power

PU1001 is the charging IC.

[BMCappelletti]

Re: HP Pavilion 17-ab091ms - white charging light, but no power

PU1001 is the charging IC.

This would be on the back of the board. A chip marked as BQ738H, which is indeed a charging chip.
I could not find continuity between the three pins on the first mosfet with pins from this one.
Do you suggest anything else I can check?

[mcplslg123]

Re: HP Pavilion 17-ab091ms - white charging light, but no power

Measure PIN 1/2/3/4/5 for ACP/ACN/CMSRC/ACDRV/ACOK,Pin16 for REGN & PIN20 FOR vcc. Lets see the measurements, then we can confirm whether charging ic is working correctly or not. Most of the times a non-functional charging ic dont let the +19V rail to pass thru.So its important.

[BMCappelletti]

Re: HP Pavilion 17-ab091ms - white charging light, but no power

Measure PIN 1/2/3/4/5 for ACP/ACN/CMSRC/ACDRV/ACOK,Pin16 for REGN & PIN20 FOR vcc. Lets see the measurements, then we can confirm whether charging ic is working correctly or not. Most of the times a non-functional charging ic dont let the +19V rail to pass thru.So its important.

Pins 1, 2 and 3 - 19,7V
Pin 5 - 2,8V
Pin 16 - 5,98V
Pin 20 - 19,7V
Could not get a read on pin 4. Multimeter only shows number 1.

[mcplslg123]

Re: HP Pavilion 17-ab091ms - white charging light, but no power

Perhaps you set your meter at 20V and that's why not getting any reading at pin4 which is supposed to be 25V approx. Everything seems fine with charger IC. Now measure the basic requirement of SIO(U5100).

PIN 11/14/20/21/26/67/68/69/81/97/107/119/123

Btw, have you flashed bios?? If not make a backup of your bios and start a request at bios section while posting your backup bios dump. When you try to switch it on,does the dc jack light blinks in quick succession?? The adapter used is HP original and rated correctly like 65W/90W??

[mcplslg123]

Re: HP Pavilion 17-ab091ms - white charging light, but no power

Measure THRM_MONITOR1 and THRM_MONITOR2 also.It could be 'coz of thermal protection as well. Hp's often have this failure.

[BMCappelletti]

Re: HP Pavilion 17-ab091ms - white charging light, but no power

Perhaps you set your meter at 20V and that's why not getting any reading at pin4 which is supposed to be 25V approx. Everything seems fine with charger IC. Now measure the basic requirement of SIO(U5100).

PIN 11/14/20/21/26/67/68/69/81/97/107/119/123

Btw, have you flashed bios?? If not make a backup of your bios and start a request at bios section while posting your backup bios dump. When you try to switch it on,does the dc jack light blinks in quick succession?? The adapter used is HP original and rated correctly like 65W/90W??

U5100

11 - 3,3V
13 - 3V
20 - 0
21 - 0
26 - 3,3V
67 - 1V
68 - 0
69 - 2,6V
81 - 0
97 - 2,8V
107 - 3,3V
119 - 0
123 - 2,4V


I didn't flash BIOS. Would need to buy some equipment to remove it and back it up.
The DC jack light does not blink. It's a solid white.
Original HP charger 120W.

[BMCappelletti]

Re: HP Pavilion 17-ab091ms - white charging light, but no power

Measure THRM_MONITOR1 and THRM_MONITOR2 also.It could be 'coz of thermal protection as well. Hp's often have this failure.

THRM_MONITOR1 3,4V
THRM_MONITOR2 I'm not sure, cause the board view I have is slightly different from the board itself.

[mcplslg123]

Re: HP Pavilion 17-ab091ms - white charging light, but no power

SIO Pin119 RSMRST# is missing. I'll strongly suggest to flash bios first before proceeding further in diagnosis.

[BMCappelletti]

Re: HP Pavilion 17-ab091ms - white charging light, but no power

SIO Pin119 RSMRST# is missing. I'll strongly suggest to flash bios first before proceeding further in diagnosis.

Ok. I bought a CH341A and will receive it today.
I'll watch some Youtube videos to check properly on how to proceed with it.
I believe the BIOS on this motherboard is this guy



Winbond 25Q64FVSIQ 1617.

[SMDFlea]

Re: HP Pavilion 17-ab091ms - white charging light, but no power

Ok. I bought a CH341A and will receive it today.
I'll watch some Youtube videos to check properly on how to proceed with it.
I believe the BIOS on this motherboard is this guy

Winbond 25Q64FVSIQ 1617.

Post a picture of U5 on the motherboard

[BMCappelletti]

Re: HP Pavilion 17-ab091ms - white charging light, but no power

Post a picture of U5 on the motherboard

That reminded me that the board is shorted. So, can a corrupted bios cause this?
I'm a noob, but I guess it does not. Or does it?

[tahc81]

Re: HP Pavilion 17-ab091ms - white charging light, but no power

Please note that BIOS chip is 1.8V device, so you'd need 1.8V SPI adapter. And no, incorrect/broken BIOS image can't cause short on power rail. If the EC BIOS is a part of it, it could make some other issues, but at least 3.3V is completely independent of BIOS and EC.

[BMCappelletti]

Re: HP Pavilion 17-ab091ms - white charging light, but no power

Please note that BIOS chip is 1.8V device, so you'd need 1.8V SPI adapter. And no, incorrect/broken BIOS image can't cause short on power rail. If the EC BIOS is a part of it, it could make some other issues, but at least 3.3V is completely independent of BIOS and EC.

I think I'm fine.



Still need to check how to do all that.
But if a broken BIOS cannot result in a short, so I don't see a point on trying to reflash it. Or did I get it wrong?

[mcplslg123]

Re: HP Pavilion 17-ab091ms - white charging light, but no power

That reminded me that the board is shorted-Where do you find it is shorted??