Acer E1-570 mb: Z5WE1 LA-9535P - problem z włączeniem / czujnikiem halla

Witam. Na stole Acer E1-570 mb: Z5WE1 LA-9535P. Laptop trafił na serwis jako nie reagujący na włącznik. Znalazłem ślad wilgoci na gnieździe taśmy płytki włącznika. Gniazdo oczyszczone - piny przemierzone z płytką włącznika - wszystko ok. Innych śladów wilgoci nie widzę. Po zwarciu dwóch pinów z prawej strony notebook startuje i działa normalnie. Zauważyłem, że po wylutowaniu układu U1 (oznaczenie x32B - czujnik Halla ? ) z płytki włącznika płyta reaguje poprawnie na włączenie. Po zastąpieniu U1 innym z podobnej płytki od Acera ( oznaczenie X322 ) ponownie brak startu. Podstawiłem całą podobną płytkę - również brak reakcji na włącznik. Bez U1 laptop działa ale po zamknięciu matrycy nie wygasza ekranu / nie hibernuje. W systemie oczywiście ustawienie na zamknięcie matrycy ustawione poprawnie. Nie bardzo wiem, co jest powodem takiego stanu rzeczy - uprzejmie proszę o pomoc w rozwiązaniu problemu.

Hello!

Measure the voltage to ground on pin 115 of KBC chip in the following cases (with the hall sensor chip U1 soldered to the board):
a) Screen cover opened.
b) Screen cover closed.

matic napisal/-a:Hello!

Measure the voltage to ground on pin 115 of KBC chip in the following cases (with the hall sensor chip U1 soldered to the board):
a) Screen cover opened.
b) Screen cover closed.

Helo matic

On the 115th leg in both cases there is 1.25V. I put a magnet from the matrix housing directly on U1 to simulate its closure.

Remeasure the voltage to ground on pin 115 of KBC chip with the small "Power button" board disconnected from the motherboard.

matic napisal/-a:Remeasure the voltage to ground on pin 115 of KBC chip with the small "Power button" board disconnected from the motherboard.

Without power button board on 115 leg kbc is 3,3V

Measure the voltages to ground on all pins of Hall sensor chip U1.
Chip U1 pin count:

matic napisal/-a:Measure the voltages to ground on all pins of Hall sensor chip U1.
Chip U1 pin count:
[ Obrazek ]

1 - 0V
2- 0,7V
3 - 1,25V

pawel1978 napisal/-a:2- 0,7V

The 3,3V power supply voltage on pin 2 of this chip is missing.

Measure the voltages to ground on pins 1, 2 of connector JPWR1 on the motherboard.
If there is 3V on both pins, the connection between this connector and small "Power button" board is broken.

matic napisal/-a:

pawel1978 napisal/-a:2- 0,7V

The 3,3V power supply voltage on pin 2 of this chip is missing.

Measure the voltages to ground on pins 1, 2 of connector JPWR1 on the motherboard.
If there is 3V on both pins, the connection between this connector and small "Power button" board is broken.

I am trying to understand how it is all connected .. in the picture pins where there is 3.3V. Pin 2 U1 is connected through a 0ohm resistor. The board is probably filled with elements depending on the laptop model. Just make a connection between the resistor and the marked 3.3V pin? It's a shame to buy a new power board

matic napisal/-a:Measure the voltages to ground on pins 1, 2 of connector JPWR1 on the motherboard.

How about that? Are there 3,3V on both pins?

If so, have you checked the continuity between pin 1 of connector JPWR1 and pin 1 on the end of FFC cable on the small "Power button" board?
And the same between pin 2 of connector JPWR1 and pin 2 on the end of FFC cable?

matic napisal/-a:

matic napisal/-a:Measure the voltages to ground on pins 1, 2 of connector JPWR1 on the motherboard.

How about that? Are there 3,3V on both pins?

If so, have you checked the continuity between pin 1 of connector JPWR1 and pin 1 on the end of FFC cable on the small "Power button" board?
And the same between pin 2 of connector JPWR1 and pin 2 on the end of FFC cable?

Sorry, I misunderstood. I give measurements from JPWR1. If I calculated correctly:

1. 3.3V
2. 0.72V
3. 1.25V
4. 1.12V
5. 3-3V
6.0V

FFC cable measured - it's ok

Measure the resistance to ground on pin 2 of connector JPWR1 in the following cases:
a) Small "Power button" board connected to the motherboard.
b) Small "Power button" board disconnected from the motherboard.

Measure the voltage to ground on pin 2 of connector JPWR1 and on pin 5 of chip PU401 in the following cases:
a) Small "Power button" board connected to the motherboard.
b) Small "Power button" board disconnected from the motherboard.

Chip PU401 pin count (top view):

matic napisal/-a:Measure the resistance to ground on pin 2 of connector JPWR1 in the following cases:
a) Small "Power button" board connected to the motherboard.
b) Small "Power button" board disconnected from the motherboard.

Measure the voltage to ground on pin 2 of connector JPWR1 and on pin 5 of chip PU401 in the following cases:
a) Small "Power button" board connected to the motherboard.
b) Small "Power button" board disconnected from the motherboard.

Chip PU401 pin count (top view):
[ Obrazek ]

- resistance to ground on pin 2 of connector JPWR1 :
a) Small "Power button" board connected to the motherboard. - resistansce high - one multimeter shows 1.2 on the 200M range, the other shows no transition
b) Small "Power button" board disconnected from the motherboard. - no transition

- voltage to ground on pin 2 of connector JPWR1 and on pin 5 of chip PU401 in the following cases:
a) Small "Power button" board connected to the motherboard. - jpwr1 - pin 2 - 0,72V; PU401 - pin 5 - 3,3V
b) Small "Power button" board disconnected from the motherboard - jpwr1 - pin 2 - 0V; PU401 - pin 5 - 3,3V

The copper path on the motherboard to the pin 2 of connector JPWR1 is broken (interrupted).

Remove some solder mask from the copper path (point "A") and measure the voltage to ground on this point. If there is 3.3V, bridge the pin 2 of connector JPWR1 to the point "A" with a jump wire.

After restoring the connection, the laptop works fine. At first glance, after cleaning the socket looked ok. Once again you are helping - thank you very much.