Hi All,
I am trying to fix my friend's all-in-one HP pavillion 23 Touchsmart AIO PC. This is an all-in-one desktop-style PC with a touch screen and no keyboard. The power supply is a laptop power supply like brick (19v, 7A) . The motherboard looks exactly like this one, https://www.empowerlaptop.com/p/hp-7...erboard-w1711/
The model number indicated on the motherboard is as follows:
708236-001
721377-501
721377-601
I would greatly appreciate if someone can find the schematic for me. I did some search but nothing, except for a sql blogger, who provides a link but has a survey-wall which I cannot get through. Also, the page does not load on PC (user-agent check ?) and seems dodgy.
I am really stuck, so please help if you can. If you are interested, please read on, I have tried to include as much information as possible. Also please feel free to ask for more info if you need.
Symptoms:
* It started showing symptoms of failed startup where you have to power on- off couple of times before it boots.
* During the failed startup there are no bios (hp screen) nor a backlight, nor any beep. The power indicator and fans startup but nothing on the display.
* I am told that on successfull boots it works fine, no screen issues.
* After an unsuccessful boot if you keep pressing the power button (ACPI) it stops. Any subsequent power press will result in a loop of starting up, powering down, as if like an over-current situation. The only way out of this is to plug out the power connector and when you press the power this time, it goes to a boot which just continues.
Things checked:
* I have disconnected disks, cdrom, digitizer and camera.
* I have reset the bios (jumper and battery waiting for almost an hour)
* Reseated memory and even the CPU.
* Removing the memory module, gives me the 5-beeps which rightly indicate missing memory module. So BIOS code and superIO seem to do their job.
* USB has power
* NO display port to try other than the LVDS connector for the builtin display.
* Power present (logic and 19v rail) in the backlight module but no enable, nor the pwm signal controlling it.
* Power not present in the LVDS connector, nor I can find an i2c clk/data (EDID) levels.
* CPU is warm not too warm.
* Had a thorough look at any blown components. None can be seen nor any water damage seen.
* No thermal camera available, so did a finger touch on caps, inductors, and power ICs, nothing is too hot.
* Checked for voltage output at the power mosfets (cpu-core, ram etc) and power seems good, although not sure if a glitch could be present.
Next steps:
* The power to LCD connector is gated by a chip RT9703 whose enable is missing. Also the EDID I2C pullups seems missing. Hopefully the schematic will show how this is wired through other GPU/VGA enable from superIO ?
* It is possible that a voltage rail is missing. I tried to find all the chips around caps and inductors. Most of them are richtek variants. They all seem to have enable, PG and power output. But it is possible that power is gated by other chips/mosfets which is best tracked using a scehamtic.
* The power rails near GPU is showing core voltage, but nothing on the screen. May be reflow the GPU ?
Any advise/insights/things to check will be greatly appreciated. Thanks so much for reading the long post.
I am trying to fix my friend's all-in-one HP pavillion 23 Touchsmart AIO PC. This is an all-in-one desktop-style PC with a touch screen and no keyboard. The power supply is a laptop power supply like brick (19v, 7A) . The motherboard looks exactly like this one, https://www.empowerlaptop.com/p/hp-7...erboard-w1711/
The model number indicated on the motherboard is as follows:
708236-001
721377-501
721377-601
I would greatly appreciate if someone can find the schematic for me. I did some search but nothing, except for a sql blogger, who provides a link but has a survey-wall which I cannot get through. Also, the page does not load on PC (user-agent check ?) and seems dodgy.
I am really stuck, so please help if you can. If you are interested, please read on, I have tried to include as much information as possible. Also please feel free to ask for more info if you need.
Symptoms:
* It started showing symptoms of failed startup where you have to power on- off couple of times before it boots.
* During the failed startup there are no bios (hp screen) nor a backlight, nor any beep. The power indicator and fans startup but nothing on the display.
* I am told that on successfull boots it works fine, no screen issues.
* After an unsuccessful boot if you keep pressing the power button (ACPI) it stops. Any subsequent power press will result in a loop of starting up, powering down, as if like an over-current situation. The only way out of this is to plug out the power connector and when you press the power this time, it goes to a boot which just continues.
Things checked:
* I have disconnected disks, cdrom, digitizer and camera.
* I have reset the bios (jumper and battery waiting for almost an hour)
* Reseated memory and even the CPU.
* Removing the memory module, gives me the 5-beeps which rightly indicate missing memory module. So BIOS code and superIO seem to do their job.
* USB has power
* NO display port to try other than the LVDS connector for the builtin display.
* Power present (logic and 19v rail) in the backlight module but no enable, nor the pwm signal controlling it.
* Power not present in the LVDS connector, nor I can find an i2c clk/data (EDID) levels.
* CPU is warm not too warm.
* Had a thorough look at any blown components. None can be seen nor any water damage seen.
* No thermal camera available, so did a finger touch on caps, inductors, and power ICs, nothing is too hot.
* Checked for voltage output at the power mosfets (cpu-core, ram etc) and power seems good, although not sure if a glitch could be present.
Next steps:
* The power to LCD connector is gated by a chip RT9703 whose enable is missing. Also the EDID I2C pullups seems missing. Hopefully the schematic will show how this is wired through other GPU/VGA enable from superIO ?
* It is possible that a voltage rail is missing. I tried to find all the chips around caps and inductors. Most of them are richtek variants. They all seem to have enable, PG and power output. But it is possible that power is gated by other chips/mosfets which is best tracked using a scehamtic.
* The power rails near GPU is showing core voltage, but nothing on the screen. May be reflow the GPU ?
Any advise/insights/things to check will be greatly appreciated. Thanks so much for reading the long post.
) 
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