Default HP X360 ( FAROE _DIS_X32_MB_MV 18742-1) no charging

[kingskie]

hello everyone,

i have a problem with HP X360 Convertible 14-dh1055TX that cannot charging.

Schematic requested - https://www.badcaps.net/forum/showthread.php?p=1239028

i measured some points on the battery pin charging on the motherboard as you can see in the attachment.

any suggestion would be appreciated.

thanks

[mon2]

Re: Default HP X360 ( FAROE _DIS_X32_MB_MV 18742-1) no charging

Does the logic board function with the use of the power adapter only?

Trace the area near the DCin connector and you should find 2*DCin mosfets.

These mosfets will be controlled very likely by a charger IC by Texas Instruments BQ series IC.

Interested in the full topside markings.

Post a clear pic of the same area with the charger IC.

Very carefully measure the voltage to ground of each pin of this charger IC. Ok go have both the adapter and the battery connected.

Post the list of measurements and the pin numbers.

[kingskie]

Re: Default HP X360 ( FAROE _DIS_X32_MB_MV 18742-1) no charging

Does the logic board function with the use of the power adapter only?

Trace the area near the DCin connector and you should find 2*DCin mosfets.

These mosfets will be controlled very likely by a charger IC by Texas Instruments BQ series IC.

Interested in the full topside markings.

Post a clear pic of the same area with the charger IC.

Very carefully measure the voltage to ground of each pin of this charger IC. Ok go have both the adapter and the battery connected.

Post the list of measurements and the pin numbers.

hi @mon2,

yes the laptop can turn on with power adapter.

here by i attach the picture with measurents that you ask.

thanks

[mon2]

Re: Default HP X360 ( FAROE _DIS_X32_MB_MV 18742-1) no charging

Review pin #4 (ACDRV) on the charger IC.

The BQ series of charger ICs like to use N-channel mosfets for the 2*DCin mosfets.

Respectively, the gate pin voltage should be higher than the voltage between source & drain pins on each DCin mosfet on N-channel devices to power on.

You presently have 19v which is the same as the source / drain pins so the mosfets should be off.

The ACDRV pin voltage should be ~25v to enable.

Remove all power. No battery.

Meter in diode mode. Short your meter probes and the meter should tone beep.

Touch one meter probe onto the 4k resistor but not the side close to pin #4 ACDRV pin on the charger IC. Touch the opposite side.

Now hunt for the DCin mosfets and touch pin #4 on the mosfet. This is the gate pin.

When you hear a tone beep, you have found the DCin mosfets.

First mosfet will be mated to the DCin connector which powers this board. We are interested in the second DCin mosfet. Both of these mosfets share the gate voltage that is driven by the ACDRV pin.

Now switch to resistance mode.

Measure the resistance across this mosfet:

Source (1-2-3) & drain (5-6-7-8)
Source & gate (4)
Gate (4) & drain

Post each measurement. We are checking if this second DCin mosfet is defective through a resistance check.

[piernov]

Re: Default HP X360 ( FAROE _DIS_X32_MB_MV 18742-1) no charging

https://www.badcaps.net/forum/showthread.php?t=90356

[kingskie]

Re: Default HP X360 ( FAROE _DIS_X32_MB_MV 18742-1) no charging

Review pin #4 (ACDRV) on the charger IC.

The BQ series of charger ICs like to use N-channel mosfets for the 2*DCin mosfets.

Respectively, the gate pin voltage should be higher than the voltage between source & drain pins on each DCin mosfet on N-channel devices to power on.

You presently have 19v which is the same as the source / drain pins so the mosfets should be off.

The ACDRV pin voltage should be ~25v to enable.

Remove all power. No battery.

Meter in diode mode. Short your meter probes and the meter should tone beep.

Touch one meter probe onto the 4k resistor but not the side close to pin #4 ACDRV pin on the charger IC. Touch the opposite side.

Now hunt for the DCin mosfets and touch pin #4 on the mosfet. This is the gate pin.

When you hear a tone beep, you have found the DCin mosfets.

First mosfet will be mated to the DCin connector which powers this board. We are interested in the second DCin mosfet. Both of these mosfets share the gate voltage that is driven by the ACDRV pin.

Now switch to resistance mode.

Measure the resistance across this mosfet:

Source (1-2-3) & drain (5-6-7-8)
Source & gate (4)
Gate (4) & drain

Post each measurement. We are checking if this second DCin mosfet is defective through a resistance check.

the pin 4 doesnt have 4K resistor on this board. the charging ic schematic that i attached before is taken from texas intrument website just for BQ24781 reference. and from this board pin 4 goes to a capasitor and the goes to pin 2. so it is different.

N.B
i dont have schematic and boardview for this motherboard. already looking everywhere but couldnt find it.

[mon2]

Re: Default HP X360 ( FAROE _DIS_X32_MB_MV 18742-1) no charging

Review mosfet pu4401. This part may be on the opposite side of the PCB.


Update: review the schematic link posted by @SMDFlea in your first post.

[kingskie]

Re: Default HP X360 ( FAROE _DIS_X32_MB_MV 18742-1) no charging

Review mosfet pu4401. This part may be on the opposite side of the PCB.


Update: review the schematic link posted by @SMDFlea in your first post.

thanks @mon2, tommorow i will check again.

[piernov]

Re: Default HP X360 ( FAROE _DIS_X32_MB_MV 18742-1) no charging

the pin 4 doesnt have 4K resistor on this board. the charging ic schematic that i attached before is taken from texas intrument website just for BQ24781 reference. and from this board pin 4 goes to a capasitor and the goes to pin 2. so it is different.

Pin 4 does have a resistor connected to it.

Review mosfet pu4401.

PU4301

[kingskie]

Re: Default HP X360 ( FAROE _DIS_X32_MB_MV 18742-1) no charging

Review pin #4 (ACDRV) on the charger IC.

The BQ series of charger ICs like to use N-channel mosfets for the 2*DCin mosfets.

Respectively, the gate pin voltage should be higher than the voltage between source & drain pins on each DCin mosfet on N-channel devices to power on.

You presently have 19v which is the same as the source / drain pins so the mosfets should be off.

The ACDRV pin voltage should be ~25v to enable.

Remove all power. No battery.

Meter in diode mode. Short your meter probes and the meter should tone beep.

Touch one meter probe onto the 4k resistor but not the side close to pin #4 ACDRV pin on the charger IC. Touch the opposite side.

Now hunt for the DCin mosfets and touch pin #4 on the mosfet. This is the gate pin.

When you hear a tone beep, you have found the DCin mosfets.

First mosfet will be mated to the DCin connector which powers this board. We are interested in the second DCin mosfet. Both of these mosfets share the gate voltage that is driven by the ACDRV pin.

Now switch to resistance mode.

Measure the resistance across this mosfet:

Source (1-2-3) & drain (5-6-7-8)
Source & gate (4)
Gate (4) & drain

Post each measurement. We are checking if this second DCin mosfet is defective through a resistance check.

hi @mon2 and @piernov,

this is the measurments for PU4031
Source (1-2-3) & drain (5-6-7-8) = 28K
Source (1-2-3) & gate (4) = 137 ohm
Gate (4) & drain (5-6-7-8) = 28k

[mon2]

Re: Default HP X360 ( FAROE _DIS_X32_MB_MV 18742-1) no charging

Flux and remove this part off the board.

Then power up without this part. Measure ACDRV pin again.

What is the voltage to ground?

Measure the mosfet resistance again while the mosfet is off the board and on your table.

Very likely that this mosfet is damaged and needs to be replaced.

[kingskie]

Re: Default HP X360 ( FAROE _DIS_X32_MB_MV 18742-1) no charging

Flux and remove this part off the board.

Then power up without this part. Measure ACDRV pin again.

What is the voltage to ground?

Measure the mosfet resistance again while the mosfet is off the board and on your table.

Very likely that this mosfet is damaged and needs to be replaced.

mosfet off the board:

Source (1-2-3) & drain (5-6-7-8) = 8.5M
Source (1-2-3) & gate (4) = OL
Gate (4) & drain (5-6-7-8) = OL

ACDRV when power on = 19V

[mon2]

Re: Default HP X360 ( FAROE _DIS_X32_MB_MV 18742-1) no charging

This mosfet is not defective. As per @Piernov's comment above, review the resistance of PU4301.

Post your measurements.

[kingskie]

Re: Default HP X360 ( FAROE _DIS_X32_MB_MV 18742-1) no charging

mosfet off the board:

Source (1-2-3) & drain (5-6-7-8) = 8.5M
Source (1-2-3) & gate (4) = OL
Gate (4) & drain (5-6-7-8) = OL

ACDRV when power on = 19V

this is the measurments for PU4031 @mon2 because PU4031 is the second mosfet.
do you want me to measure the first mosfet?

[mon2]

Re: Default HP X360 ( FAROE _DIS_X32_MB_MV 18742-1) no charging

Yes, do so. Also check the resistance to ground of the 2nd mosfet pads. Something is making the 2nd mosfet look defective when it is on the logic board.

Check the voltage of REGN pin on the charger IC.

It should be ~6 volts.

[kingskie]

Re: Default HP X360 ( FAROE _DIS_X32_MB_MV 18742-1) no charging

Yes, do so. Also check the resistance to ground of the 2nd mosfet pads. Something is making the 2nd mosfet look defective when it is on the logic board.

Check the voltage of REGN pin on the charger IC.

It should be ~6 volts.

yes @mon2 REGN voltage is 6V as you can see from my previews posting picture.

first mosfer measurements:
Source (1-2-3) & drain (5-6-7-8) = 0.8 ohm
Source (1-2-3) & gate (4) = 137 ohm
Gate (4) & drain (5-6-7-8) = 137 ohm

[mon2]

Re: Default HP X360 ( FAROE _DIS_X32_MB_MV 18742-1) no charging

Flux and remove this first mosfet and check the mosfet again after it is removed.

[kingskie]

Re: Default HP X360 ( FAROE _DIS_X32_MB_MV 18742-1) no charging

Flux and remove this first mosfet and check the mosfet again after it is removed.

first mosfet off board measurements:
Source (1-2-3) & drain (5-6-7-8) = 0.9 ohm
Source (1-2-3) & gate (4) = 138 ohm
Gate (4) & drain (5-6-7-8) = 138 ohm

[mon2]

Re: Default HP X360 ( FAROE _DIS_X32_MB_MV 18742-1) no charging

To confirm, these are the measurements of the removed mosfet while it is on your work table?

If yes, then this mosfet is defective and must be replaced.

Perform the same resistance check of the mosfet pads on the PCB from where this mosfet was removed. The readings should now be much higher for the resistance checks.

Also test the mosfet #2 pcb pads in the power path for the same reason.

[kingskie]

Re: Default HP X360 ( FAROE _DIS_X32_MB_MV 18742-1) no charging

To confirm, these are the measurements of the removed mosfet while it is on your work table?

If yes, then this mosfet is defective and must be replaced.

Perform the same resistance check of the mosfet pads on the PCB from where this mosfet was removed. The readings should now be much higher for the resistance checks.

Also test the mosfet #2 pcb pads in the power path for the same reason.

yes the measurements before is from mosfet on my tabe.

here is the measurements of first mosfet pads:
Source (1-2-3) & drain (5-6-7-8) = 9.3M
Source (1-2-3) & gate (4) = 8.8M
Gate (4) & drain (5-6-7-8) = 15M

here is the measurements of second mosfet pads:
Source (1-2-3) & drain (5-6-7-8) = 9.2M
Source (1-2-3) & gate (4) = 8.8M
Gate (4) & drain (5-6-7-8) = 15M

so that means that mosfet is failing right?

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