Hp probook 450 g3 not turn on

[lapfix]

Re: Hp probook 450 g3 not turn on

No my friend , let's start by steps , we have a pb to fix at the charge circuit before , so remplace PQ 26 with a good N-channel one , you can find it at many other boards

[arber1232]

Re: Hp probook 450 g3 not turn on

No my friend , let's start by steps , we have a pb to fix at the charge circuit before , so remplace PQ 26 with a good N-channel one , you can find it at many other boards

ok bro i change and i have 19 v in gate

[lapfix]

Re: Hp probook 450 g3 not turn on

For N-Channel you must have +24v at the gate , So PU14 voltages :
pin 28/ 24 / 6 /5

[arber1232]

Re: Hp probook 450 g3 not turn on

i solved problem is pin midle of charger problem

[lapfix]

Re: Hp probook 450 g3 not turn on

Nice , so can you give us now this voltage
U13 =
Pin 42 = ADP_A_ID
Pin 44 = OCP_A_IN
Maybe it help another friend

[arber1232]

Re: Hp probook 450 g3 not turn on

[QUOTE=lapfix;1042138]Nice , so can you give us now this voltage
U13 =
Pin 42 = ADP_A_ID
Pin 44 = OCP_A_IN
Maybe it help another friend[/
my laptop has another problem now when i use it with caricature the laptop stays for about 10 minutes and turns off ... when i use it only with battery the laptop works very well ... i noticed that PU17 gets very hot when i use the laptop with caricature

[huzo]

Sorry for lifting an old thread, but i have simmilar issues with this board, when i plug the charger, the LED on the charger goes white and at the same time 4 time amber blinks while white is glowing , also poweer button is white for that time and then it goes off...i have 3.3V and 5V, PU12 =1.8V, and 2.2V at the power button...and that's it...the board doesn't turn on,2.2V goes of when put to ground,KBC gets that signal, adapter signal is present on the KBC, what else to look for? Can anyone explain how to read the power on sequence? Signals like PWR_GOOD_3 should be low or high?

[mcplslg123]

Signals like PWR_GOOD_3 should be low or high-HIGH

[huzo]

PWR_GOOD_3 on PU5 is low...0V,so that is ok?i don't know what else to try...i tried a few dumps, no change...

[mon2]

No, not good. Power good signals are open drain lines that float when power is ok. The external pull up resistor will then park the line to a soft high level. If stuck low, the line is being pulled low by the regulator or the external pull up is not to a logic high voltage level.

[huzo]

So i figured... i don't get the pgd signals obviously...so i am missing a voltage?I don't know how to read the startup sequence from the image few posts above , can anyone explain? There are no shorts on the board, except low resistance (5 Ohm) on the +VCC_core,but i injected 1V, and get 200mA draw...so no short...

[jasko_jacker]

So i figured... i don't get the pgd signals obviously...so i am missing a voltage?I don't know how to read the startup sequence from the image few posts above , can anyone explain? There are no shorts on the board, except low resistance (5 Ohm) on the +VCC_core,but i injected 1V, and get 200mA draw...so no short...

you refer to POWER BLOCK DIAGRAM at pg 64 ? I don't see any startup sequence on the schematic

[huzo]

yes,that....sorry,i am self taught and still learning ...what to look for next?

[huzo]

So i have a few of this laptops with the same problem...i connect the charger and the white light goes on for 2 seconds and amber blinks 3 times and that's it...power connector has 2.2V, i have 5.4V and 3.37V...i get 3.3V on bios chip when cable connected , but not when i press power button...all seems to be fine, but it won't start... and i have 7 of them with same problem

Pin 42 = ADP_A_ID is 1.6V
Pin 44 = OCP_A_IN is 0V

can anyone help? i've donated to the site because it's always helpfull, so i am hopping to be helpfull now also

[mcplslg123]

The basic steps for troubleshootinga dead laptop is always the same, so just stick to basics.

01.Physical observation under microscope
02.Resistance to GND readings on all coils
03.Resistance to GND readings for switched rails like 3VS/5VS(Look for dc-dc converter switches)
04.Flash BIOS
05.Check RTC Section for RTCRST#/SRTCRST#
06.Consumption on dc supply in standby mode
07.Voltage,if any on coils.

[huzo]

Yeah i did all that...all voltages present,no shorts...i went through the standard procedure....

the issue is solved finnaly...it was the charger ... i got them without chargers, and i had only 45W for testing , and this board needs 65W... what a noob