Tuesday, April 12, 2016

Lenovo ThinkPad X250 – AC adapter voltage testing – How to test the battery pack – How to test the backup battery - How to reset the Laptop factory default – Laptop repair and service

Category: Laptop repair and Service 

Contents of this article 

  • How to test the battery pack 
  • How to test the AC adapter 
  • How reset to factory default 

Lenovo ThinkPad X250

How to test the Power system 
To verify if the battery packs and the power adapter are functional, do the following:
1. Turn off the computer.
2. Connect the ac power adapter.
3. Turn on the computer. If the computer can be turned on, it means that either the battery pack or the ac power adapter is functional.
4. Insert a straightened paper clip into the emergency reset hole to reset the computer. If the computer is still powered on, it means that the ac power adapter is functional.
5. Turn off the computer.
6. Disconnect the ac power adapter and turn on the computer. If the computer can be turned on, it means that the battery pack is functional.
If you suspect that the power problem is caused by a specific power device, refer to the appropriate
checkout item in the following list:
“Checking the ac power adapter”
“Checking operational charging”
“Checking the coin-cell battery”
Checking the ac power adapter
You are here because the computer fails only when the ac power adapter is used.
If the system status indicator (the indicator in the ThinkPad logo or the indicator in the center of the power button) does not blink three times when an ac power source is connected, check the power cord of the ac power adapter for correct continuity and installation.
1. Unplug the ac power adapter cable from the computer.
2. Measure the output voltage at the plug of the ac power adapter cable.
Note: Output voltage of pin 2 of the ac power adapter might differ from the one you are servicing.
3. If the voltage is not correct, replace the ac power adapter.
4. If the voltage is acceptable, replace the system board.
Note: Noise from the ac power adapter does not always indicate a defect.
Checking operational charging
To check whether the batteries charge properly during operation, do the following:
1. Discharge the batteries until the remaining battery power is less than 50%.
2. Connect the computer to ac power to charge the batteries. If the battery status icon in the Windows notification area indicates that the batteries are not charging, remove the batteries and let them return to room temperature.
3. Reinstall the batteries. If the batteries are still not charging, replace the batteries.
4. Check the battery status icon again. If the same error still exists, replace the system board.
Checking the external battery pack
To check for detailed battery status information, do the following:
For 7 operating system: Open the Power Manager program and click the Battery tab.
For 8 and 8.1 operating systems: Open the Lenovo Settings program and click Power.
Note: If the battery pack becomes hot, it may not be able to charge. Remove it from the computer and leave it at room temperature for a while. After it cools down, reinstall and recharge it.
To check the battery pack, do the following:
1. Power off the computer.
2. Remove the battery pack and measure the voltage between battery terminals 1 (+) and 7 (-). See the following figure:
3. If the voltage is less than +11.0 V dc, the battery pack has been discharged. If the voltage is still less than +11.0 V dc after recharging, replace the battery pack.
4. If the voltage is more than +11.0 V dc, measure the resistance between battery terminals 5 and 7.
The resistance must be 4 to 30 K Ω. If the resistance is not correct, replace the battery pack. If the resistance is correct, replace the system board.
Checking the coin-cell battery
To check the coin-cell battery, do the following:
1. Disable the built-in battery.
2. Remove the coin-cell battery.
3. Measure the voltage of the coin-cell battery.
If the voltage is correct, replace the system board.
If the voltage is not correct, replace the coin-cell battery.
If the coin-cell battery discharges quickly after replacement, replace the system board.
Resetting the computer to the factory default settings
If you want to recycle your computer or just start over, you can reset your computer to the factory default settings. Resetting the computer will reinstall the operating system, reinstall all the programs that came with your computer, and reset all the settings to the factory default settings.
Attention: If you reset the computer to the factory default settings, all your personal files and settings will be deleted. To avoid data loss, make a backup copy of all the data that you want to keep. To reset your computer to the factory default settings, do the following.
1. Depending on the operating system, do one of the following:
For 8:
Move your pointer to the top-right or bottom-right corner of the screen to display the charms. Click
Settings >  Change PC settings >  General.
For 8.1:
Move your pointer to the top-right or bottom-right corner of the screen to display the charms. Click Settings > Change PC settings > Update and recovery > Recovery.
2. In the Remove everything and reinstall Windows section, click Get started. Then click Next to confirm the operation.
3. Depending on your needs, do one of the following:
To perform a quick format, click Just remove my files to start the process. The process will take several minutes.
To perform a complete format, click Fully clean the drive to start the process. The process will take several hours.
4. Follow the instructions on the screen to reset your computer to the factory default settings.