HP Gaming 16-a0006nl - no charge / no power

[ShocK-306HDi]

Hi friend, I've this notebook HP Gaming 16-a0006nl with QUANTA DAG3JBMB8D0 that won't power on.
I start checking first mosfet and they seems to be ok.
On power button I get 3 that go to 0 on pressing, and come to 3v on release.
After I check charge ic that is BQ738H
I write here measure with battery and ac

19
19
19
25
3

1.9
0
3.1
3.1
1

11
11
11
gnd
0

6
10
11
11
19

I've 0 on pin 7 IOUT and on pin 15 LODRV.
What can I check.
Thanks for your help

[mon2]

Can you reformat your measurement table and post it again? Which pins were measured?

[ShocK-306HDi]

Yes yes of course, sorry !

1 ACN: 19
2 ACP: 19
3 CMSRC: 19
4 ACDRV: 25
5 ACPRES: 3

6 ACDET:1.9
7 IOUT: 0
8 SDA: 3.1
9 SCL: 3.1
10 ILIM: 1

11 BATDRV: 11
12 SRN: 11
13 SRP: 11
14 GND: 0 gnd
15 LODRV: 0

16 REGN: 6
17 BTST: 10
18 HIDRV: 11
19 PHASE: 11
20 VCC: 19

[mon2]

Are you using the proper rated power adapter?

The following is too low:

6 ACDET:1.9

Thus should be 2v4 or higher.

[ShocK-306HDi]

I'm using Regulated Power Supply set on 19.5 v

[mon2]

ACDET must be 2v4 or higher to enable. This value is from a resistor based voltage divider.

Would you have access to the official power adapter?

[ShocK-306HDi]

Yes, I've checked with official HP AC Adapter, but not changing....same 1.9v , I also measure 2 resistor connected on ACDET line and they are OK, I also have a capacitor, I would to try remove it ?

[mon2]

Can you link the schematic for this board? (only if it is posted in the schematic forum)

Also, can you share the 2 resistor values that are on the ACDET line? Need the high side and low side resistor values. You can measure the resistance to ground on ACDET and the measurement should be close to the low side of the resistor value. If not, then the capacitor is affecting the resistance. For now, leave the capacitor in circuit but we may have to review these resistors.

Do you have a stable 19v5 as the input to the logic board? This voltage does not drop during use?

[mon2]

See attached. With no power to the board, measure the resistance with your meter across PR1031.

What is the resistance?

Repeat with testing across PR1032.

If you are comfortable, use low air pressure + flux and carefully move the resistors so they can be measured. Do not rush it else the parts can go flying off the board. Suspecting that you have a fault here and the ACDET voltage is below the required threshold of 2v4.

The measurement without the parts being in-circuit is always more accurate than being in-circuit.

[ShocK-306HDi]

Okok
Measuring resistances isulated from circuit I've PR1032 with 49 kohm, on PR1031 I've 0,430 mhom

[ShocK-306HDi]

Measuring PR1031 without power I get 247 kohm
PR1032 49 kohm as in schematic
Abnormal is PR1031

[mon2]

Voltage @ ACDET is too low so there is still some other factor here. If PR1031 is lower than the schematic, the voltage of ACDET will be higher. At the very least, we need ACDET to be 2v4 or a bit higher.

Do you have other resistors available to you?

Use this online resistor based voltage divider calculator to configure this network so that ACDET is higher than 2v4. Apply the resistor values available to you for PR1031.

Summary : Decrease the high side resistor value till the 2v4 threshold is met or is a bit higher. Only then will this charger IC accept the external power adapter supply to be suitable to power this board and charge the battery.

Voltage Divider Conversion Calculator | DigiKey

[ShocK-306HDi]

Yes, I can take other resistor to from other bad board....but I've never done this
If I found an exact 430k resistor as in schematic for PR1031, that would be much better...

[mon2]

Best to practice, practice on a donor board. According to the calculator, these values and this adapter voltage will not be high enough @ ACDET pin. However, you can test the parts you have.

[ShocK-306HDi]

If I inject 2.4 volts on ACDET with my regulated dc power supply, it is not the same thing ?

[mon2]

That should be ok as well. The ACDET is just that, a detection that the power adapter is present and the resistors dial down the high voltage to a safe value.

[mcplslg123]

What is the voltage on AD_ID? While using dc supply are you using PS_ID converter for HP160W.The usuall PS_ID converter for HP's is 90W-so using dc supply the mb wont power on at all. Moreover,with gaming m/b's you need to set your dc supply at 21V and not 19.5V. Better to use HP original adapter and measure AD_ID voltage. Does the dc jack light glows?

[ShocK-306HDi]

That should be ok as well. The ACDET is just that, a detection that the power adapter is present and the resistors dial down the high voltage to a safe value.

I tried, but nothing changed, I inject 2.4 volt with my power supply without changes, battery not charge, if I measure with tester on BATT+


On AD_ID nothing... 0 volt.
I've tried set power supply to 21v but nothing change
On DC Jack it doesn't turn on the light

I see the light, only when I unplug power supply cable from dc jack, it blink just one time and stop.

[mon2]

Hp Laptop Adapter ID pin Resister Value #lciit Laptop Repair Tutorial (youtube.com)

[ShocK-306HDi]

I want to thank the users mon2 e mcplslg123 for the great help in solving the problem with this laptop, with a 150w HP power supply the computer started working again.
On the AD_ID pin I get 12v, the computer charges, turns on and everything works.
Thanks friends