HP Pavilion x360 14m-dh0000 no power

[arber1232]

Re: HP Pavilion x360 14m-dh0000 no power

Check if the removed diode @ D4301 is defective.

Meter in diode mode, check if the diode conducts in one direction with your meter and should block in the other direction. Need to understand why the diode was heating up.

Also, where is 'Ed 4302'? Is if 'PD4302' ?

diode is ok i measure not shorts and in multimeter is ok . Now after i removet ED 4302 diode not heat


this is ED4302 is near battery

[mon2]

Re: HP Pavilion x360 14m-dh0000 no power

Got it - thanks. That is an ESD diode array.

To confirm, if D4301 is REMOVED, then ED4302 is not heating up?

But diode D4301 measure to be ok on your work table?

In diode mode, it should conduct in one direction with readings like 0.4 to 0.6 but OL in the opposite direction. Can you confirm it?

[arber1232]

Re: HP Pavilion x360 14m-dh0000 no power

Got it - thanks. That is an ESD diode array.

To confirm, if D4301 is REMOVED, then ED4302 is not heating up?

But diode D4301 measure to be ok on your work table?

In diode mode, it should conduct in one direction with readings like 0.4 to 0.6 but OL in the opposite direction. Can you confirm it?

the diode was heated at the moment when I injected 2 v into the resistor r4503. I believe that you get hot because of ED4302. .. i measure diode and it iis o.140

[arber1232]

Re: HP Pavilion x360 14m-dh0000 no power

now i not understand why voltage is not stably change from 3,2 v to 2,5 v etc

[mon2]

Re: HP Pavilion x360 14m-dh0000 no power

The LDO rail has a max current rating. If the current rating (ie. downstream load) is exceeded, the voltage will drop.

Much like us lifting weights (although have pulled my back recently), you have limits. If you try to lift too much, you can only lift a smaller amount.

So this means, this power rail still is faced with a larger than expected load.

There is a possibility that this regulator is defective but not sure of this status, yet.

Does the LDO heat up ?

[arber1232]

Re: HP Pavilion x360 14m-dh0000 no power

The LDO rail has a max current rating. If the current rating (ie. downstream load) is exceeded, the voltage will drop.

Much like us lifting weights (although have pulled my back recently), you have limits. If you try to lift too much, you can only lift a smaller amount.

So this means, this power rail still is faced with a larger than expected load.

There is a possibility that this regulator is defective but not sure of this status, yet.

Does the LDO heat up ?

ldo ? i not understand . ic not heat
can we say kbc is problem ?

[mon2]

Re: HP Pavilion x360 14m-dh0000 no power

It could be. Not a KBC expert. Wait on others to comment but yes, who ever is on this power rail is pulling it down and exceeding the max current rating for this LDO rail of the regulator.

That is, someone is out of spec. Is the KBC getting warm ?

If you feel comfortable, remove the series resistor on this LDO to remove the pin 17 from the load.

Then use your external power supply @ 3v3 setting and apply to the downstream load. This is because your external power supply can offer higher current.

What is the current draw on your external power supply?

Is anyone heating up ? Perhaps the KBC ?

Do wait on others to comment but as noted, someone on this leg of the circuit is not consuming the correct current so the power rail is being pulled down.

[arber1232]

Re: HP Pavilion x360 14m-dh0000 no power

It could be. Not a KBC expert. Wait on others to comment but yes, who ever is on this power rail is pulling it down and exceeding the max current rating for this LDO rail of the regulator.

That is, someone is out of spec. Is the KBC getting warm ?

If you feel comfortable, remove the series resistor on this LDO to remove the pin 17 from the load.

Then use your external power supply @ 3v3 setting and apply to the downstream load. This is because your external power supply can offer higher current.

What is the current draw on your external power supply?

Is anyone heating up ? Perhaps the KBC ?

Do wait on others to comment but as noted, someone on this leg of the circuit is not consuming the correct current so the power rail is being pulled down.

i try with power supply but current in power supply is 0.030 ah and kbc or other component not heat

[arber1232]

Re: HP Pavilion x360 14m-dh0000 no power

i see now after Pu4301 ( the first mosfet in dc in ) voltage change ftom 19,5v to 11 etc voltage is not stably...Now i turn on laptop i inject 19.5 volt after Pu4401 and laptop turn on

[mon2]

Re: HP Pavilion x360 14m-dh0000 no power

Measure the voltage to ground of each pin on PU4401 mosfet. Use your original adapter.

Source (1-2-3)
Gate (4)
Drain (5-6-7-8)

[arber1232]

Re: HP Pavilion x360 14m-dh0000 no power

s --134 kohms
g-0l
d-2.5 mohms but goin up


sorryy pu4401 is

s-2,5ohms
g-0l
d-0.6mohms

[mon2]

Re: HP Pavilion x360 14m-dh0000 no power

Measure the voltage to ground of each pin on PU4401 mosfet.

Not resistance.

Meter in DC volts (30v or higher is ok). Then red meter probe on pin to test. Black meter probe to ground.

For this mosfet (N-channel) to turn ON, the GATE pin #4 should be ~25 volts.

[arber1232]

Re: HP Pavilion x360 14m-dh0000 no power

s-19.5v but not stably
g-25.4v but no stably
d-19.5 but not stably

voltage after pu4301 change not stably

[mon2]

Re: HP Pavilion x360 14m-dh0000 no power

Ok. Very possible that this mosfet is defective or something on the load side is shorted.

Remove all power.

Meter in RESISTANCE mode.

Check the resistance across the mosfet pins as follows:

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

Post each measurement. If any of these checks are with a low resistance, the mosfet is defective and should be replaced.

[arber1232]

Re: HP Pavilion x360 14m-dh0000 no power

source (1-2-3) & drain (5-6-7-8)=3.2mohm
source (1-2-3) & gate (4)=0l
gate (4) & drain (5-6-7-8)=0l

i change mosfet but is same voltage not stably

[arber1232]

Re: HP Pavilion x360 14m-dh0000 no power

if i inject 19.5 volt in drain pu4401 laptop work ok and voltage is ok

[mon2]

Re: HP Pavilion x360 14m-dh0000 no power

The mosfet looks ok but something is wrong. Trace the power path from where you are injecting to the dc adapter connector. Measure each voltage to ground.

[mon2]

Re: HP Pavilion x360 14m-dh0000 no power

Also check the resistance (without power) of the first DCin mosfet. It may be defective.

[arber1232]

Re: HP Pavilion x360 14m-dh0000 no power

Also check the resistance (without power) of the first DCin mosfet. It may be defective.

is good not lower resistance , i changed fore sure but not change anything

[mon2]

Re: HP Pavilion x360 14m-dh0000 no power

Are you using a suitable power adapter?

If the mosfets are good but only external power supply works then the power adapter is not with the correct power rating.