Acer Predator PH317-51 Nie startuje, brak obrazu

Witam

Acer Predator Helios 300 PH317-51
Płyta LA-E911P C5MMH/C7MMH

Płyta podłączona pod zasilacz pobór skacze w granicy 0 do 8mA, przy próbie załączenia zwiększa się do 28mA po czym po chwili wyłącza się do początkowego stanu.
Pomiary ne cewkach

Cewka rezystancja Standby ON
PL402 24KR 0V 3,3V
PL301 6MR 0,21V 0,21V
PL404 50KR 5V 5V
PL1602 52R 0V 0V
PL1502 1,9R 0V 0V
PL1503 1,9R 0V 0V
PL809 11R 0V 0V
PL803 1,9R 0V 0V
PL804 1,9R 0V 0V
PL805 1,9R 0V 0V
PL806 3,2R 0V 0V
PL807 3,2R 0V 0V
PL602 42,4R 0V 1,02V
P1502 101R 0V 0V

Zawartość biosu podmieniona bez zmian, co można jeszcze sprawdzić by potwierdzić uszkodzenie KBC lub PCH, czy posiada ktoś tabele Power Sequence?

Pozdrawiam

Płyty w nowszych Acerach są wrażliwe na napięcie zasilania, być może masz kiepskie przewody a przez to spadek napięcia. Podnieś napięcie zasilania i zobacz czy się nie poprawi.

Podaje zasilanie 20V, zmiana na 20,5 nie wpływa na zmianę zachowania płyty.

Measure the voltages to ground on listed points, when the machine is turned on (power consumption is 28mA):
- On pins 3, 8, 14 of chip UQ1.
- On pins 7, 8, 11, 12, 18 of chip PU501.

N
UQ1
pin 3 > 0V
pin 8 > 0V
pin 14 > 0V

PU501
pin 7 > 0V
pin 8 > 0V
pin 11 > 5,1V
pin 12 > 5,1V
PIN 18 > 4,68V

Measure the voltages to ground on pins 9, 15, 19, 67, 110, 115, 119 of KBC chip before pressing to the power button (machine is turned off).

Measure the voltages to ground on pins 114, 122 of KBC chip in the following cases:
a) Power button released.
b) Power button pressed.

Now disconnect the power supply, wait about two minutes, reconnect the power supply and perform the following measurements:
Measure the voltages to ground on pins 6, 13, 14, 32, 95, 100, 104, 108, 112, 116, 123 of KBC chip in the following cases:
c) Before pressing to the power button (machine is turned off).
d) After pressing to the power button (power consumption is 28mA).

Voltages on KBC
9 >> 3,32 V
15 >> 0 V
19 >> 0 V
67 >> 3,32V
110 >> 3,27 V
115 >> 3,29 V
119 >> 3,29 V

114 power button released 3,32V power button pressed 0,00 V
122 power button released 0,00 V power button pressed 3,32 V

Pin KBC >> Before pressing >> After pressing
6 >> 0,02 V >> 0,00 V
13 >> 0,02 V >> 0,00 V
14 >> 0,01 V >> 0,00 V
32 >> 0,00 V >> 0,00V
95 >> 0,00 V >> 0,00V
100 >> 0,00 V >> 3,33 V
104 >> 3,27 V >> 3,35 V
108 >> 0,35 V >> 0,35 V
112 >> 3,28 V >> 3,36 V
116 >> 0,00 V >> 0,00 V
123 >> 0,03 V >> 0,00 V

Measure the voltages on pin 9 of PU401, PU402.

voltage on PU401 before pressing the button 0V after pressing power 3,34 V
voltage on PU402 before pressing the button 3,29 V after pressing power 3,33 V

Measure the voltages on pin 122 of KBC.

before pressing the button 0V after pressing power 3,35 V

Measure the voltage to ground on pin 12 of KBC chip in the following cases:
c) Before pressing to the power button (machine is turned off).
d) After pressing to the power button (power consumption is 28mA).

c) 0,01 V
d) 0,00 V

Set your multimeter to the diode test mode and measure the voltage drops to ground on pins 6, 12, 13, 14, 19, 32, 95, 116, 123 of KBC chip with the positive (red) probe connected to ground.

6 >> 0,50 V
12 >> 0,53 V
13 >> 0,50 V
14 >> 0,50 V
19 >> 0,50 V
32 >> 0,56 V
95 >> 0,50 V
116 >> 0,48 V
123 >> 0,50 V

Replace the PCH chip.