HP Probook 470 G3 (Quanta X63C DAX63CMB6C0) - Not powering on with Adapter

With PQ25 removed from the board the readings on the pads are

D= 18.6V
S= 19V
G= 25V

Replace the charger chip PU14 (BQ24780S).

I replaced PU14 and now here are the readings from the 5 mosfets, with just adapter (No Battery).

PQ21:
D -> 19.8V
S -> .200V
G -> .200V

PQ22:
D -> .200V
S -> 0V
G -> 0V

PQ25:
D -> 19.8V
S -> .200V
G -> .230V

PQ26:
D -> 19.8V
S -> 19.8V
G -> 26V

PQ27:
D -> 19.8V
S -> 19.8V
G -> 26V

The laptop will now power on from adapter alone. Also it will charge the battery. However i am still geting some strange behaviour with the LED on the DC Jack.

With HP laptops when only the adapter is inserted alone (No Battery) there should be a solid white LED on DC Jack. With this laptop once you plug adapter in the white LED shows for ~3 seconds then cuts off completly. Only the light on the Power Button will come on once the power button is pressed.

The orange LED will show fine when adapter is plugged along with the battery and is charging.

The voltages on all transistors are okay now.

Measure the voltage to ground on pin 8 of BIOS chip, when the laptop is turned off.

ok, pin 8 of the BIOS is 3.4V

Also the white LED will flash for 1 second when you power off the laptop too.

Try to reflash the BIOS chip. Don't forget to save the old dump.

Ok, because laptop is powering on ok, i updated the BIOS with HP Softpaq (01.39 Rev.A).

But the issue still presists, no white LED on DC Jack when the adapter is plugged in, only for 3 seconds straight after plugging in, and 1 second after laptop powers off.

The LED pins on the connector CN13
pin 7 = 3.6V
pin 8 = 3.3V

The KBC is certainly defective.

Really, just on the white LED circuit? everything else seems to be working ok.

Is it a programmable KBC? it is NPCE586HA0MX

Measure the voltages on pins 113, 120 of KBC.

Pin 113 = 3.6V
Pin 120= 3.3V

Would it be possible there is somthing wrong with the LED circuits? I can not see any White LED signal in the schematics. just Green and Amber.

Replace the KBC chip.

If I'm not mistaken, that KBC chip doesn't require programming.

Ok, i found one on the Allegro.pl site, but i do not read Polish, and dont know if they ship outside Poland.

Is there any other place to buy from in Europe that you may know of?

and dont know if they ship outside Poland.

Yes, they send outside of Poland.

Sorry for the delay, i was waiting for the KBC from China.

I have swapped the KBC but still the same issue is there. No white LED on DC jack when the adapter is plugged in. The laptop powers on and works, just not with the white LED.

It does show Amber LED when battery is inserted and charging.

I dont know what it could be.

Measure the voltages to ground on pins 39, 42, 44 of KBC chip with connected charger only (without battery).

measurements from KBC are

pin 39 = 1.48v
pin 42 = 2.55v
pin 44 = 0v

Should pin 44 (OCP_IN_ADC) have any voltage?

If I understood you correctly now everything works fine, except the LED near the DC jack?

Yes that is correct, just the white LED is not present on the DC jack when it is inserted. It will appear for around 2 seconds when plugged in, then goes off.. and it will flash again for 1 second when you power off the laptop. Everything else seems to be working fine.

I suppose it is not a major issue, i am just curious to why it is not working 100%. If you have no idea why that is ok i will finish the job and let the customer know, as it is past my capabilities. thanks for your input.

Have you replaced the charger chip PU14 with exactly the same as it was the original one (if I'm not mistaken it should be BQ24780S)?

If so, install a "BatteryMon" software and post a screen, how it detects the battery ("Battery Info" button). Do that, when the power supply + battery are connected.