ASUS N501VW - nie reaguje na włączenie

Model: Asus UX501V
Platforma: N501VW
Rev: 2.0

KBC: IT8995E-128 CXS

Witam,

Laptop trafił do mnie z objawami:

Po podłączeniu zasilacza od razu świeci włącznik power, CapsLock oraz F2.
Po rozkręceniu laptopa zauważyłem że złącza matrycy nie ma.. kilka padów jest naruszonych i naderwanych.

Co zrobiłem:
-Programowanie Bios:
Po tym zabiegu diody nie świecą ale laptop nie chce się uruchomić, nie reaguje na power.

- po wgraniu starego obrazu Bios również nie ma żadnej reakcji.

Pomiary:
Na cewkach obecne: 3,3V, 5V, 1V
Rezystancje w normie.

KBC:
Pin 56 of KBC chip:
a) Power zwolniony - 2,5V
b) Power wciśnięty- 0V

Pin 110 of KBC chip:
a) Power zwolniony - 3,27V
b) Power wciśnięty - 0V

Napięcia względem GND KBC:
p.12 - 1,76V
p.26 - 3,28V
p.35 - 0V
p.57 - 0V
p.96 - 0,00V
p.109 - 0,0V

Nie wiem dlaczego nie mogę się połączyć z KBC... Svod zgłasza zajętość... "ITE is busy"

Update:
-PU8600 był wymieniany i wlutowany na odwrót, na kluczu 8600 było zwarcie do bramki. Wymieniłem klucze i czekam na przetwornice która powodowała zwarcie.

Pytanie czy to napięcie 1,2V powinno być obecne na PL8600?? To zasilaniu również RAMU??

dernis ha scritto:Pytanie czy to napięcie 1,2V powinno być obecne na PL8600??

The voltage on coil PL8600 should apeear after pressing to the power button (when the machine is turned on).

dernis ha scritto:To zasilaniu również RAMU??

Yes, it is a RAM power supply.

thx.

i found an integrated circuit.
it was OK ..

after connecting the power adapter and attempting to turn it on. The resistances are back to low values.

-PQ8600
whether the resistance between pin 3-> 4 = 1,1Ohm is good??

The same situation on PQ9301... there is the same richtek that I also changed.

Remove the transistor PQ8600 from the board and measure the resistance between pins 1, 4 of this transistor out of the board.
Also measure the resistance between pads 1, 4 on the place of that transistor on the board (without transistor).

1.5 Ohm is nowhere..

if you desolder and re-solder it is fine. Resistance 1 and 4 = 10 kOhm.

In the circuit PU9300 and PU8600.

As if there was something in the discharge of the gate.

Update:

ok ... the reason was a damaged bios IC ...

I do not have an image on the matrix ... it is on HDMI.

I am asking for help

Measure the voltages to ground on pins 4, 10, 13, 14, 17 of LVDS connector J4502, when the machine is turned on with connected LCD screen and with disconnected HDMI monitor.

4 - 3,3V
10 - 19,3V
13 - 0V
14 - 0V
17 - 0V

Perform the following measurements with connected LCD screen and with disconnected HDMI monitor:
- Measure the resistance to ground on pin 1 of chip U4501.
- Measure the voltages to ground on pins 1, 3, 5 of chip U4501, when the machine is turned on.

Resistance pin 1 = 0,84kOhm

U4501 - Voltages:
1 - 0V
3 - 0V
5 - 3,3V

should D45103, D45104, D45105 be mounted?

dernis ha scritto:should D45103, D45104, D45105 be mounted?

These diodes are an "suppressor" protection diodes and are often omitted by the manufacturer to reduce costs.

Make sure the LVDS connector is correctly soldered to the motherboard and all broken pads are repaired.
If it is okay, check the LVDS cable and try with another LCD screen.

13 "pad" was broken, no improvement after continuity repair.

I noticed that the matrix was changed.
I'm waiting for the tape.

on a new tape ... On U4501:
Pin 1 -3,3V
Pin 3 - 3.3V
appears for 2-3 seconds and drops to 0V. The matrix is ​​dark but polarizes.


I changed the bios and I always have 3.3V on U4501 pin 1 and 3 after turning on but no image...

Try with another LCD screen (matrix). Make sure that you will use a replacement LCD screen with an UHD resolution 3840 x 2160.

hmm ... such a matrix is ​​mounted ... N156HGE-E2 rev C2.. it does not look like UHD ...

dernis ha scritto:such a matrix is ​​mounted ... N156HGE-E2 rev C2.. it does not look like UHD ...

You may have right.
As far as I found about this model it exists in two versions - with FHD (1920 x 1080) or with UHD (3840 x 2160) matrix.

dernis ha scritto:I noticed that the matrix was changed.

The matrix may have been previously replaced with the wrong one.

However, measure the voltages to ground on pins 10, 13, 14, 15, 17 of LVDS connector, when the machine is turned on.

Ok.

10-19V
13-0V
14-0V
15 - 2.5V
17 - 3.3 V.

There is no voltage on the L1201 coil ... should there be?

dernis ha scritto:There is no voltage on the L1201 coil ... should there be?

I think it is normal. That voltage probably appears only, when the Thunderbolt interface is in use.

If you are sure that all of the connections to the LVDS connector are properly rebuild, try with another matrix. First try with a FHD (1920 x 1080) matrix. If it will be the same also try with an UHD (3840 x 2160) matrix.

3 - matrices
3 - tapes

the same reaction on all of them ... can I check something else? Connections of the connector checked .. it's ok.

14 pin LVDS to GND = 7 Ohm ... is it correct?

dernis ha scritto:14 pin LVDS to GND = 7 Ohm ... is it correct?

No, it is not normal. Disconnect the LVDS cable from the board and remeasure the resistance to ground on pin 14 of LVDS connector.
If the resistance will still be around 7Ω, check if the diode D45103 is present on the board. If so, remove this diode from the board and check the resistance again. If the resistance will increase to the high value (to the kΩ range or greater), this diode is damaged, otherwise the chip U4502 is damaged.

u4502 was damaged ... after replacement, very high resistance .. but still no improvement