HP 830 G5 nie odpala, nie reaguje na wlacznik, miga dioda zasilania.

HP Elitebook 830 G5
MB: 6050A2930901-MB-A01(A1)
CPU: I5-[8250U]
EC: NUVOTON [NPCX797HA0BX]

Po podłączeniu zasilacza:
1) zapala się dioda biała power i świeci światłem ciągłym
3) dioda czerwona na tej samej diodzie power miga non stop (bez żadnych przerw, które wskazywały by na jakiś konkretny błąd)
4) dioda capslock świeci się światłem ciągłym

Bios i EC podmieniony na inny znaleziony w sieci, zachowanie takie samo. Napiecia 3,3V oraz 5V występują. Na kości BIOS na 8 nóżce opornośc w normie (kohm).
Oporności cewek poniżej.

Hello!

Is 3V present on the power button?
Does the machine turn off and stay turned off, if you hold down the power button for a few seconds?

Is 3V present on the power button?

Yes, 3,3V is present on power button.

Does the machine turn off and stay turned off, if you hold down the power button for a few seconds?

Yes, after connecting power supply, the motherboard takes around 0,015A. After pressing the power button, the current drops to 0,006A and the leds stops blinking.

Please, post a clear picture of marked area of the board:

Measure the voltages to ground on pins 1, 3, 5, 7, 8, 14 of chip U7002 in the following cases:
a) Machine turned off (power consumption is 6mA).
b) Machine turned on (power consumption is 15mA).

Turned on 15mA
1 - 5,2V
3 - 3,3V
5 - 0V
7 - 5,2V
8 - 0V
14 - 5,2V

Turned off - 6mA
1 - 0V
3 - 0v
5 - 0v
7 - 0v
8 - 0v
14 - 0v

Looks like there is no EN signal on 5 pin. Question is, which chip is responsible for that signal.

- Check, if the quartz X4750 oscillates.
- Measure the resistances to ground on pins 5, 8 of chip U7000.

Check, if there is the same chip as U7002. If so, also measure the voltages on this chip under the same conditions.

- Check, if the quartz X4750 oscillates.

Sorry, no oscilloscope

- Measure the resistances to ground on pins 5, 8 of chip U7000.

U7000 has only 5 legs.

Check, if there is the same chip as U7002. If so, also measure the voltages on this chip under the same conditions.

ON
1 - 3,3V
3 - 0V
5 - 3,3V
7 - 3,3V
8 - 3,3V
14 - 0V

OFF
1 - 0v
3 - 0v
5 - 0v
7 - 0v
8 - 0v
14 - 0v

lgolebio написав:

matic написав:- Check, if the quartz X4750 oscillates.

Sorry, no oscilloscope

If so, measure the voltages to ground on both pins of this quartz with a multimeter.

lgolebio написав:

matic написав:- Measure the resistances to ground on pins 5, 8 of chip U7000.

U7000 has only 5 legs.

Sorry, my fault I meant U7002.

lgolebio написав:

matic написав:Check, if there is the same chip as U7002. If so, also measure the voltages on this chip under the same conditions.

ON
1 - 3,3V
3 - 0V
5 - 3,3V
7 - 3,3V
8 - 3,3V
14 - 0V

Measure the resistances to ground on pins 3, 14 of this chip.

U7002
5,8 - 120kohm

x4750
1- 323mV
2 - 0V
3 - 0V
4 - 410mV

U7002
3 - 117kohm
14 - 8,9kohm