Asus F550L na płycie X550LD Rev 2.0 - nie uruchamia się, brak 3,3 i 5V

Laptop Asus F550L
Płyta główna X550LD Rev 2.0
Płyta się nie uruchamia, brak reakcji na włącznik, brak napięć 3,3V oraz 5V

Jak dostałem laptopa, to grzał się układ PU8100 - wymieniłem na nowy uP1589Q (dla pewności dwukrotnie), potem po podłączeniu zasilacza na chwilę zaświecały się PQ8102 i PQ8103 (P2003BEA) - wymieniłem na AON7408 z płyty dawcy.
Teraz już po podłączeniu zasilacza nic się nie grzeje.
PR8101 na 1 nodze dostaje 18,42V ale na nodze nr 2 jest 4,13V (to chyba nie jest prawidłowe napięcie? ) bez PU8100 jest tam ~19V...


Pomiary:
PJP8502, PQ8100, PQ8103 - 18,49V
PSL8101, PL8101, PSL8100, PL8100 - 0V

Oporność :
PL8101 ~11Ω
PL8100 ~16kΩ
PSL8101 ~33,5kΩ (tu prawidłowo powinno być 3,3V, prawda?)
PSL8100 ~49,70kΩ (tu prawidłowo powinno być 5V, prawda?)
n11 i n12 układu PU8300 (mierzone na PR8309 oraz PR8310 - 1,7Ω

Zrobiłem próbę zwarciową. Przyłożyłem 5V do PJP8101 oprócz PU8100 grzeją się także 2 rezystory w okolicy PU8300 są to PR8310 oraz PR8309

Będę wdzięczy o pomoc w dalszej diagnozie...

Sasni написав:PR8101 na 1 nodze dostaje 18,42V ale na nodze nr 2 jest 4,13V (to chyba nie jest prawidłowe napięcie? )

Hello!
Yes, that's definitely not normal. It means the resistor PR8101 (1Ω/5%, package 0603) is damaged. Replace it.

Sasni написав:bez PU8100 jest tam ~19V...

DO NOT connect the power supply to the board with the chip PU8100 removed from the board. This way you may cause additional damage to the board.

Sasni написав:PSL8101 ~33,5kΩ (tu prawidłowo powinno być 3,3V, prawda?)
PSL8100 ~49,70kΩ (tu prawidłowo powinno być 5V, prawda?)

Yes, exactly.

Sasni написав:Zrobiłem próbę zwarciową. Przyłożyłem 5V do PJP8101 oprócz PU8100 grzeją się także 2 rezystory w okolicy PU8300 są to PR8310 oraz PR8309

Remove the chip PU8300 from the board and remeasure the resistance to ground on coil PL8101.
And also do not connect the power supply to the board with the chip PU8300 removed.

Thank you for your help.

matic написав:the resistor PR8101 (1Ω/5%, package 0603) is damaged. Replace it.

WOW I measured it after removing it. he was 69Ω...

matic написав:Remove the chip PU8300 from the board and remeasure the resistance to ground on coil PL8101.

after removing the PU8300, the resistance increased to ~20kΩ

I understand that I have to look for "uP1565" (PU8300)?

Sasni написав:I understand that I have to look for "uP1565" (PU8300)?

Yes, exactly.

Also measure the resistance to ground on pin 11 of chip PU8100 (if you have the PU8100 still removed from the board, you can measure the resistance between the big central pad and pin 11 of this chip). This resistance should be in kΩ range, otherwise the chip PU8100 is also damaged.

matic написав:Also measure the resistance to ground on pin 11 of chip PU8100 (if you have the PU8100 still removed from the board, you can measure the resistance between the big central pad and pin 11 of this chip). This resistance should be in kΩ range

~37kΩ

I ordered a new chip, I'll put it in, measure the resistance on legs 11 and 12 and if it's high, can I connect the power supply?

Sasni написав:

matic написав:Also measure the resistance to ground on pin 11 of chip PU8100 (if you have the PU8100 still removed from the board, you can measure the resistance between the big central pad and pin 11 of this chip). This resistance should be in kΩ range

~37kΩ
I ordered a new chip, I'll put it in, measure the resistance on legs 11 and 12

I don't know if we understand each other. I'm talking about the resistance on the chip PU8100 (not the PU8300).
The PU8300 (uP1565) is damaged in any case and needs to be replaced.

Sasni написав:can I connect the power supply?

Only with both chips - PU8100 and PU8300 soldered to the board.

matic написав:I'm talking about the resistance on the chip PU8100 (not the PU8300).

I think I understood correctly, I measured the resistance at the red point.

So the resistance is fine.
As suggested solder the chip PU8100 back to its place (if you haven't already done it) and solder the new chip PU8300. Than connect the power supply to the board and test it.

After mounting the PU8100 and PU8300 and connecting the power supply, the following heat up:
PU8100 (strongest)
D2201
Point smaller core U0301 (probably at VCCRTC point)

There is already ~19V on leg 11 of the PU8100
I think that the PU8100 system is working properly only under load.
The voltage on the PSL8100 is ~5V
The PSL8107 voltage is ~2V (it should be 3.3V)

I measured this diode, voltage drop between points

1-3 = 0,239V
2-3 = 0,295V
3-1 = OL
3-2 = -0,26V

Should I replace the D2201 ?
Can I remove it for a while and connect the power supply?

Measure the resistance to ground on pin 3 of diode D2201.

matic написав:Measure the resistance to ground on pin 3 of diode D2201.

6,26MΩ

Sasni написав:[ Obrazek ]
Can I remove it for a while and connect the power supply?

Yes, remove that diode and check, if the PU8100 still heats up.

After desoldering the D2201, the PU8100 system no longer heats up.
3.3V and 5V voltages present.
On pin 3 of the D2201 diode 1.26V
On pin 1 - 3.3V

PU8100 heats up very gently - it is not felt with a finger. Only visible on a thermal camera.
Also, U0301 (same corner as before) ~30 degrees
and the U3301 chip - these are temperatures around 30-35 degrees. I honestly don't need a memory card reader...

After applying the voltage, the LEDs light up as shown in the picture below.

Perform a short circuit test described here on pin 3 of diode D2201. For a short circuit test limit the voltage to 3V.
Check, if any component on the board heats up. If not, what electrical current flows from the laboratory power supply in this case?

Unfortunately, the CPU gets hot
I understand it's over. Thank you for your help.