• ASUS Vivobook M7600R (M6500RC R2.0) - 19V Power Rail Not generated, AC-Detect

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#21 Re: ASUS Vivobook M7600R (M6500RC R2.0) - 19V Power Rail Not generated, AC-Detect


by matic 28 August 2024, 08:23
Measure the voltages to ground on pins 14, 15 of charger chip.

Re: Re: ASUS Vivobook M7600R (M6500RC R2.0) - 19V Power Rail Not generated, AC-Detect


by Google Adsense [BOT] 28 August 2024, 08:23

#22 Re: ASUS Vivobook M7600R (M6500RC R2.0) - 19V Power Rail Not generated, AC-Detect


by KenM0560 28 August 2024, 08:33
Voltage to ground of charger chip
14 = 1.5v
15 = 1.5v

Resistance to ground for pin 14 and 15 is 133k ohms

#23 Re: ASUS Vivobook M7600R (M6500RC R2.0) - 19V Power Rail Not generated, AC-Detect


by matic 28 August 2024, 10:29
KenM0560 wrote:[ Obrazek ]
Please, also post a picture of another side of the board.

#24 Re: ASUS Vivobook M7600R (M6500RC R2.0) - 19V Power Rail Not generated, AC-Detect


by KenM0560 28 August 2024, 12:43
matic wrote:Please, also post a picture of another side of the board.


Image
Image
Image

#25 Re: ASUS Vivobook M7600R (M6500RC R2.0) - 19V Power Rail Not generated, AC-Detect


by KenM0560 29 August 2024, 13:17
When using a USB-C adapter the 19v line does come up, and the battery starts to charge. But still same symptoms with regular adapter.

#26 Re: ASUS Vivobook M7600R (M6500RC R2.0) - 19V Power Rail Not generated, AC-Detect


by matic 30 August 2024, 07:34
Measure the voltage to ground on any pin of the current sense resistor you marked in the picture with a regular adapter connected.
KenM0560 wrote:[ Obrazek ]


#27 Re: ASUS Vivobook M7600R (M6500RC R2.0) - 19V Power Rail Not generated, AC-Detect


by KenM0560 30 August 2024, 10:35
With the regular adapter connected both sides measure 1.5V

#28 Re: ASUS Vivobook M7600R (M6500RC R2.0) - 19V Power Rail Not generated, AC-Detect


by matic 30 August 2024, 12:55
Please, post a clear picture of marked area of the board.
Image

#29 Re: ASUS Vivobook M7600R (M6500RC R2.0) - 19V Power Rail Not generated, AC-Detect


by KenM0560 30 August 2024, 20:46
No problem, here is the area. Both of the gates connect to the bottom of the resistor in the second picture, and the chip to the left has 1.8v on pin 3 and 5, and 0v on the rest.
Image

Image

#30 Re: ASUS Vivobook M7600R (M6500RC R2.0) - 19V Power Rail Not generated, AC-Detect


by matic 2 September 2024, 08:31
KenM0560 wrote:[ Obrazek ]
Measure the voltages to ground on all pins of 5-pin chip marked "SCG" visible in the picture.

#31 Re: ASUS Vivobook M7600R (M6500RC R2.0) - 19V Power Rail Not generated, AC-Detect


by KenM0560 2 September 2024, 09:06
The chip marked SCG starting from bottom right pin in orientation of the picture (could not see dot to mark pin1 on the chip)

1= 1.47V
2= 0V
3= 1.7V
4= 1.8V
5= 3.3V

#32 Re: ASUS Vivobook M7600R (M6500RC R2.0) - 19V Power Rail Not generated, AC-Detect


by matic 2 September 2024, 10:46
KenM0560 wrote:could not see dot to mark pin1 on the chip
This chip is in a classic SOT323-5 (also known as SOT353) package with a standard pinout (picture below), so you counted the pins correctly.
Image

Measure the values of resistors "A" and "B" marked in the following picture. Both resistors must be removed from the board to measure their actual value.
Image

#33 Re: ASUS Vivobook M7600R (M6500RC R2.0) - 19V Power Rail Not generated, AC-Detect


by KenM0560 2 September 2024, 14:27
matic wrote:so you counted the pins correctly.

At least my memory is still holding up lol.

Off board
Resistor A = 600k ohms
Resistor B = 470k ohms

There is around 50k ohms fluctuation either way when measuring.

#34 Re: ASUS Vivobook M7600R (M6500RC R2.0) - 19V Power Rail Not generated, AC-Detect


by matic 3 September 2024, 07:27
KenM0560 wrote:There is around 50k ohms fluctuation either way when measuring.
Test your meter with a known good resistor with the resistance around 470k-1MΩ.
If you have the fluctuation as well, try to replace the batteries in your meter.

Also post a picture of this area of the board with resistors A, B and chips marked "SCG" and another marked "8KB" near it removed form the board (I want to see the path of the copper traces under these components).

#35 Re: ASUS Vivobook M7600R (M6500RC R2.0) - 19V Power Rail Not generated, AC-Detect


by KenM0560 3 September 2024, 08:54
After changing the battery in the multi meter, i am now getting a more steady reading of

Resistor A = 1M ohm
Resistor B = 700k ohms

No problem, here is the area without Resistor A,B and ICs SCG and 8KB on board.
Image

#36 Re: ASUS Vivobook M7600R (M6500RC R2.0) - 19V Power Rail Not generated, AC-Detect


by matic 3 September 2024, 12:38
Use a continuity tester and check, if the left pin of resistor "A" is connected to the ground.

#37 Re: ASUS Vivobook M7600R (M6500RC R2.0) - 19V Power Rail Not generated, AC-Detect


by KenM0560 3 September 2024, 13:03
Yes it is connected to ground.

#38 Re: ASUS Vivobook M7600R (M6500RC R2.0) - 19V Power Rail Not generated, AC-Detect


by matic 3 September 2024, 13:17
Solder all components back to the board, except the resistor A and measure the following voltages to ground:
- On pins 1, 3, 4, 5 of chip marked "SCG".
- On pins 1, 2, 3, 4, 6 of chip marked "8KB".

#39 Re: ASUS Vivobook M7600R (M6500RC R2.0) - 19V Power Rail Not generated, AC-Detect


by KenM0560 3 September 2024, 14:36
All components are back on board apart from Resistor A.

SCG
---
1= 1.4V
3= 1.7V
4= 3.1V
5= 3.3V

8KB
---
1= 0V
2= 3.1V
3= 0V
4= 0V
6= 0V

#40 Re: ASUS Vivobook M7600R (M6500RC R2.0) - 19V Power Rail Not generated, AC-Detect


by matic 4 September 2024, 08:07
Measure the voltages to ground on pins 1, 4, 5 of transistors "C", "D" under the same conditions (without the resistor A).
Image

Re: ASUS Vivobook M7600R (M6500RC R2.0) - 19V Power Rail Not generated, AC-Detect


by Google Adsense [BOT] 4 September 2024, 08:07
This topic is marked as ARCHIVAL. Please only reply if your message contains the solution (Terms and Conditions p. 12.1).

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