Saturday, March 12, 2016

LENOVO LAPTOP – Lenovo yoga 300 - Disassembling procedure – Battery removal - LCD screen removal – AC adaptor testing procedure – Laptop repair and service

Category: Laptop Repair and Service 

Contents of this article

  • AC adapter testing procedure 
  • Removing the back cover 
  • Removing the battery 

Lenovo yoga 300

Power system checkout
To verify a symptom, follow the steps below:
1. Turn off the computer.
2. Connect the AC adapter.
3. Make sure that power is supplied when you turn on the computer.
4. Turn off the computer.
5. Disconnect the AC adapter.
6. Make sure that the battery pack supplies power when you turn on the computer.
If you suspect a power problem, see the appropriate power supply checkout:
“Checking the AC adapter”
“Checking operational charging”
Checking the AC adapter
You are here because the computer fails only when the AC adapter is used.
# If the power-on indicator does not turn on, check the power cord of the AC adapter for correct continuity and installation.
To check the AC adapter, follow the steps below:
1. Unplug the AC adapter cable from the computer.
2. Measure the output voltage at the plug of the AC adapter cable. See the following figure:
Note: Output voltage for the AC adapter pin No. 2 may differ from the one you
are servicing.
3. If the voltage is not correct, replace the AC adapter.
4. If the voltage is acceptable, do the following:
# Replace the system board.
Note: Noise from the AC adapter does not always indicate a defect.
Checking operational charging
To check whether the battery charges properly during operation, use a discharged battery pack or a battery pack that has less than 50% of the total power remaining when installed in the computer.
Perform operational charging. If the battery status indicator or icon is not lit, remove the battery pack and let it return to room temperature. Reinstall the battery pack. If the charge indicator or icon is still off, replace the battery pack. If the charge indicator is still not lit, replace the system board.
Restore of factory default
The Lenovo Yoga 300 computer comes with pre-installed OneKey Recovery System.In order to save application files and the initial backed up files of the system, the hard disk in a Lenovo computer includes a hidden partition when it is shipped. If you need to restore the system to the point of your first boot up, just enter Lenovo OneKey Recovery System and run System Recovery.
How to remove Base cover
Remove the screws 1. Then remove the base cover 2
How to remove  Battery pack
Unplug the battery connector 1 and remove the screws 2. Then remove the
battery pack in the direction shown by arrow 3
How to remove  Hard disk drive
Detach HDD connector in the direction shown by arrow 1.
Remove the frame fixing screws 2

Remove the hard disk drive in the direction shown by arrow 3.
How to remove  LCD unit
Remove the screws 1
Open the hinges, detach LCD cable connector in the direction shown by arrow
2, then remove the upper case from the LCD unit in the direction shown by
arrow 3.
How to remove  System board
Remove screws 1. Unplug speakers connector and DC-IN connector in the
direction shown by arrow 2. Detach touch pad connector, keyboard and IO
board connectors in the directions shown by arrows 3 and 4.
Remove the system board in the direction shown by arrow 6.