Hello everyone,
I like to repair everything I can get my hands on.
A friend gave me a laptop that fell down while it was switched on.
Now the display remains dark and the laptop no longer boots up.
Since my English is not so good, I worked with a translation tool. Please excuse me if something is not translated correctly.
Normally this device is not in a price category where you have to grit your teeth, but I really want to find the error and learn something in the process
Details of the device:
Manufacturer: Lenovo
Type: Ideapad 1 15IGL7
Mainboard: JS47R&JS57R NM-E791 Rev. 1.0
CPU: Intel N4120
Storage device: eMMC 128GB soldered
RAM: 4GB soldered
What have I noticed so far?
- All voltages seem to be present at the power inductors.
- None of the power transistors have a short circuit
- JRTC 3,04V
- The battery LED is yellow when the battery is charging, white when the battery is full.
- CPU has approx. 40°C without cooler
- No other warm or hot components can be seen with a thermal imaging camera.
- An external monitor also shows no image
- If the battery is not connected, the power LED flashes permanently, with battery the LED lights up but there is a kind of reset every 30 seconds.
- Only with battery the power LED goes out after 30 seconds
- I have read out the bios and it is identical to one from this forum
My assumption after a fall on the floor is that a cold solder joint or crack in the circuit board has occurred.
Unfortunately, my knowledge is not that profound. Can someone tell me what I could check further and/or how to check BIOS, it8227e-128 and CPU for function (all voltages seem to be OK here too) ?
how to check the cpu reset signal?
i have boardview but no wiring diagram
my available equipment:
multimeter
oscilloscope
thermal imaging camera
Thank you all
I like to repair everything I can get my hands on.
A friend gave me a laptop that fell down while it was switched on.
Now the display remains dark and the laptop no longer boots up.
Since my English is not so good, I worked with a translation tool. Please excuse me if something is not translated correctly.
Normally this device is not in a price category where you have to grit your teeth, but I really want to find the error and learn something in the process
Details of the device:
Manufacturer: Lenovo
Type: Ideapad 1 15IGL7
Mainboard: JS47R&JS57R NM-E791 Rev. 1.0
CPU: Intel N4120
Storage device: eMMC 128GB soldered
RAM: 4GB soldered
What have I noticed so far?
- All voltages seem to be present at the power inductors.
- None of the power transistors have a short circuit
- JRTC 3,04V
- The battery LED is yellow when the battery is charging, white when the battery is full.
- CPU has approx. 40°C without cooler
- No other warm or hot components can be seen with a thermal imaging camera.
- An external monitor also shows no image
- If the battery is not connected, the power LED flashes permanently, with battery the LED lights up but there is a kind of reset every 30 seconds.
- Only with battery the power LED goes out after 30 seconds
- I have read out the bios and it is identical to one from this forum
My assumption after a fall on the floor is that a cold solder joint or crack in the circuit board has occurred.
Unfortunately, my knowledge is not that profound. Can someone tell me what I could check further and/or how to check BIOS, it8227e-128 and CPU for function (all voltages seem to be OK here too) ?
how to check the cpu reset signal?
i have boardview but no wiring diagram
my available equipment:
multimeter
oscilloscope
thermal imaging camera
Thank you all