hp omen 15-dh1015nl does not turn on

[mon2]

Flip the board over and post clear pics of the area under the PUB1 charger IC. We are hunting for the DCin mosfets. These parts may be close to the DCin power connector as well.

[giulio93]

Flip the board over and post clear pics of the area under the PUB1 charger IC. We are hunting for the DCin mosfets. These parts may be close to the DCin power connector as well.

I find the DCin mosfet, what are we looking for? The have a regular 19V in and out and 25V on the gate

[mon2]

Continue to test this power path. What are the voltages on the 2nd DCin mosfet?

Since the gate pins are shared, the 2nd gate pin should also be the same voltage. Share the source & drain pin voltages on the 2nd dcin mosfet.

[giulio93]

I have the DC_IN voltage on pin 31 and 32

[giulio93]

Continue to test this power path. What are the voltages on the 2nd DCin mosfet?

Since the gate pins are shared, the 2nd gate pin should also be the same voltage. Share the source & drain pin voltages on the 2nd dcin mosfet.

mon2 all the values you are asking me for I already shared. I have the 19V on the 2nd dcin_mof and 25V on the gates. Now I understood we have a problem with the line on the PIN1. But without a boardview how can I find the colprut?

[mon2]

Do you still have PUB1 @ 85C?

Pin 1? On PUB1? The voltage is in range because of the voltage divider built by the resistors which lowers the Vin of the power adapter.

[giulio93]

Do you still have PUB1 @ 85C?

Pin 1? On PUB1? The voltage is in range because of the voltage divider built by the resistors which lowers the Vin of the power adapter.

No now, i don't have 85C on the PUB1 since I chenged it. I don't undestand, so 2,66 V is ok for PIN1?

[mon2]

Based on the example circuit from the other vendors (Acer) - they used 2 resistors on pin 1. We are assuming that this vendor used a similar circuit. In short, Pin 1 is used to sense if the power adapter is with the proper voltage range. Often the voltage should be 2v7 or higher to gauge the adapter is ok.

The final test is that ACOK is being configured to a logic '1' = OK. Otherwise, this line would be parked to a logic low = '0'.

[giulio93]

Based on the example circuit from the other vendors (Acer) - they used 2 resistors on pin 1. We are assuming that this vendor used a similar circuit. In short, Pin 1 is used to sense if the power adapter is with the proper voltage range. Often the voltage should be 2v7 or higher to gauge the adapter is ok.

The final test is that ACOK is being configured to a logic '1' = OK. Otherwise, this line would be parked to a logic low = '0'.

The last sentence is a confirm that both PIN1 and PIN2 are ok or not. I am not understanding

[mon2]

Sorry - It is ok. Pin 1 is the (lower) voltage from the power adapter. Then Pin 2 is the ACOK output from this charger IC to announce if the Pin 1 voltage is OK or not. Since Pin 2 is a logic '1', the adapter voltage is OK.

If the logic board is not turning on, test each and every inductor on the board to confirm their voltages are OK. Each inductor is linked to a local power rail. If they are, review to reflash the motherboard with a known good bios image.

[giulio93]

Sorry - It is ok. Pin 1 is the (lower) voltage from the power adapter. Then Pin 2 is the ACOK output from this charger IC to announce if the Pin 1 voltage is OK or not. Since Pin 2 is a logic '1', the adapter voltage is OK.

If the logic board is not turning on, test each and every inductor on the board to confirm their voltages are OK. Each inductor is linked to a local power rail. If they are, review to reflash the motherboard with a known good bios image.

I have no power to the I/O chip and on the bios chip and so on.
Anyway now i will measure the voltage and send a pic of them. Are you going to be online tomorrow to continue the troubleshooting?

[giulio93]

Sorry - It is ok. Pin 1 is the (lower) voltage from the power adapter. Then Pin 2 is the ACOK output from this charger IC to announce if the Pin 1 voltage is OK or not. Since Pin 2 is a logic '1', the adapter voltage is OK.

If the logic board is not turning on, test each and every inductor on the board to confirm their voltages are OK. Each inductor is linked to a local power rail. If they are, review to reflash the motherboard with a known good bios image.

I took the measures. Without the battery plugged in I have 0V on each inductor. (che grey chocke). With battery plugged in (V_batt is 11.5) i have the 2 tension in the pics. I dont remember if i said it or not so i will say again now. The pc stops works due to a screw fell into the PUB1 zone.

[mon2]

According to elektroda, the LA-H492p schematic can be used to reference the LA-J662P.

Locate the following power supply ICs - these are used to power your missing bios power rails.




On the inductor with the 0v, measure the resistance to ground. Post the resistance value.

[giulio93]

According to elektroda, the LA-H492p schematic can be used to reference the LA-J662P.

Locate the following power supply ICs - these are used to power your missing bios power rails.




On the inductor with the 0v, measure the resistance to ground. Post the resistance value.

How Can I find the 2 power supply ICs? How can I recognise them? Furthermore, if i don't remember wrong, i should check the I/O chip power before the bios chip. Isn't it?
Here the resistance reading of the inductors. No one reads 0Ohm or near it

[mon2]

Hunt path should be -> search for the part using the white silk screening on the PCB. So search for PU301 (as an example).

Plan B is to review the schematic -> review the part number -> ideally, there should be a public datasheet for the component on the internet -> download for a review. Note the topside markings from the datasheet and hunt for this same part on your board.

See attached for PU301.

[giulio93]

Hunt path should be -> search for the part using the white silk screening on the PCB. So search for PU301 (as an example).

Plan B is to review the schematic -> review the part number -> ideally, there should be a public datasheet for the component on the internet -> download for a review. Note the topside markings from the datasheet and hunt for this same part on your board.

See attached for PU301.

Here the V on PU301
P1 0V
P2 P3 P4 P5 19,98V
P6 0V
P9 0V
P11 4,6V
P12 4,6V
P13 0V
P14 0V
P17 0V
P19 0V
P20 0V
The other pin are GND or NC from the schem.
From these measurment are we understand that this chip is not working properly or is missing some "enable" line that activates it?
Thanks again

[Sephir0th]

There is almost no way for Pin 12 to measure higher than 3.3V, since this enable is directly asserted from the EC.

Get used to double-check your measurements please and also try to avoid bridging pins together, depending on the thickness of your probes.

[giulio93]

There is almost no way for Pin 12 to measure higher than 3.3V, since this enable is directly asserted from the EC.

Get used to double-check your measurements please and also try to avoid bridging pins together, depending on the thickness of your probes.

I swear i triple check the measures but i get wrong all 3 times. the PIN12 is 0V

[giulio93]

Now i supposed the problem is the missing EN1, correct?

[giulio93]

Looking at the PU301 diagram i think it's a problem also having 0V at pin1 and 6. Am i correct?