Laptop Asus F554L
Motherboard X555LA Rev 3.3 ;P/N : 60NB0810-MB1610 with soldered Intel i3 5010U. no graphic CPU
I received the laptop as working, but with 3 problems :
1) Laptop display not working, but ok with external monitor connected via HDMI
2) Keyboard not working, but ok with external USB keyboard
3) Laptop starts up and boots windows as soon as charger is connected, without pressing power on switch. Laptop always automatically reboots after shutdown or pressing power off switch if charger is connected. Everything ok if battery only is connected : it is possible to power on /power off by switch and does not reboot by itself after windows shutdown.
I used boardview and repair guide attached to https://www.badcaps.net/forum/showthread.php?t=70958
Problem 1 solved by fixing the display LED backlight circuitry, as laptop display was working but without backlight.
Problem 2 solved by cleaning the keyboard connector.
Problem 3 is still open and driving me crazy. Every thing works fine and I managed to install and use Windows 10 without a problem. Battery charges fine. But if AC charger present laptop automatically boots itself.
So far I did the following checks/tests:
- There is no CMOS battery on this board, but I tried to reset config by shorting many times JRST2201 and JRST2202
- Cleaned MB with isoprophilic alcohol:no change
- Looked for some autostart parameter in BIOS : found none.
- Reset BIOS to deafults and tried to disable Fast Start, lid open and all boot parameters : no change
- Removed all connectors from MB : no change
- Tried a different power supply or new battery: no change
- Replaced SIO chip with new IT8585E FXA (which regularly reprogrammed itself at first boot)
- Installed latest BIOS using ASUS EZ flash utility : no change
- Checked 3.3v on power on switch and signal and it goes low as expected when pressed (same as line PWR_SW#) . The PWR_SW# line never goes down by itself when attaching or using the charger,but goes low as expected when pressing the switch both with mains and on batteries.
- Line PM_PWRBTN# regularly goes to 0v for a short while after pressing the switch and goes back to 3.3v. At this point it stays at 3,3V if on mains or goes to 0V if on battery (I don't know if this is correct)
Windows has nothing to do with the problem as it happens even with just the MB.
It looks like the typical problem which can be solved by resetting the CMOS or flashing the bios or replacing SIO, but not this time.
After fixing many laptops which could not boot I am running out of ideas on how to repair this one which auto starts !?!
Any help is highly appreciated
Motherboard X555LA Rev 3.3 ;P/N : 60NB0810-MB1610 with soldered Intel i3 5010U. no graphic CPU
I received the laptop as working, but with 3 problems :
1) Laptop display not working, but ok with external monitor connected via HDMI
2) Keyboard not working, but ok with external USB keyboard
3) Laptop starts up and boots windows as soon as charger is connected, without pressing power on switch. Laptop always automatically reboots after shutdown or pressing power off switch if charger is connected. Everything ok if battery only is connected : it is possible to power on /power off by switch and does not reboot by itself after windows shutdown.
I used boardview and repair guide attached to https://www.badcaps.net/forum/showthread.php?t=70958
Problem 1 solved by fixing the display LED backlight circuitry, as laptop display was working but without backlight.
Problem 2 solved by cleaning the keyboard connector.
Problem 3 is still open and driving me crazy. Every thing works fine and I managed to install and use Windows 10 without a problem. Battery charges fine. But if AC charger present laptop automatically boots itself.
So far I did the following checks/tests:
- There is no CMOS battery on this board, but I tried to reset config by shorting many times JRST2201 and JRST2202
- Cleaned MB with isoprophilic alcohol:no change
- Looked for some autostart parameter in BIOS : found none.
- Reset BIOS to deafults and tried to disable Fast Start, lid open and all boot parameters : no change
- Removed all connectors from MB : no change
- Tried a different power supply or new battery: no change
- Replaced SIO chip with new IT8585E FXA (which regularly reprogrammed itself at first boot)
- Installed latest BIOS using ASUS EZ flash utility : no change
- Checked 3.3v on power on switch and signal and it goes low as expected when pressed (same as line PWR_SW#) . The PWR_SW# line never goes down by itself when attaching or using the charger,but goes low as expected when pressing the switch both with mains and on batteries.
- Line PM_PWRBTN# regularly goes to 0v for a short while after pressing the switch and goes back to 3.3v. At this point it stays at 3,3V if on mains or goes to 0V if on battery (I don't know if this is correct)
Windows has nothing to do with the problem as it happens even with just the MB.
It looks like the typical problem which can be solved by resetting the CMOS or flashing the bios or replacing SIO, but not this time.
After fixing many laptops which could not boot I am running out of ideas on how to repair this one which auto starts !?!
Any help is highly appreciated
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