Tuesday 29 May 2018

Lenovo ThinkPad P50s – How to test the AC adapter – How to make a recovery disc – How to test the backup battery


Lenovo ThinkPad P50s:  Power system checkout
To verify if a battery and ac 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 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 the battery is functional.
If you suspect a power problem, see the appropriate one of the following power supply checkouts:
“Checking the ac power adapter”
“Checking the battery and 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 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.
To check the ac power adapter, do the following:
1. Unplug the ac power adapter cable from the computer.
2. Measure the output voltage at the plug of the ac power adapter cable. See the following illustration.
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 the operational charging
To check whether the battery charges properly during operation, do the following:
1. Discharge the battery until the remained battery power is less than 50%.
2. Perform operational charging. Click the battery status icon in the Windows notification area to display detailed battery information. If it indicates that the battery is not charging, replace the battery.
3. Check the battery status again. If the same error still exists, replace the system board.
Checking the coin-cell battery
To check the coin-cell battery, do the following:
1. Disable the built-in battery. See “Disabling the built-in battery”
2. Remove the coin-cell battery. See “1080 Coin-cell battery”
3. Measure the voltage of the coin-cell battery. See the following illustration
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.
Restoring the factory contents by using the product Recovery Disc Set
During the recovery process, all data on the drive will be deleted. If possible, copy any important data
or personal files that you want to keep onto removable media or a network drive before you start the
recovery process.
The recovery process takes one to two hours to complete. The length of time depends on the method you use. If you use product Recovery Disc Set, the recovery process takes about two hours.
1. Connect an external CD/DVD drive.
2. Make the CD/DVD drive the first startup device in the startup sequence using the following procedure:
a. Open the ThinkPad Setup program and select Startup >  Boot.
b. Select the CD/DVD drive as the 1st Boot Device.
3. Insert the bootable recovery disc into the CD/DVD drive.
4. Start the computer from the external CD/DVD drive.
5. When promoted, select your language and click Next.
6. Read the license and accept the terms and conditions. Then follow the instructions on the screen.
7. If the Recovery Disc Set contains a Supplemental Recovery Disc, insert it when prompted and click Yes.
Note: Not all Recovery Disc Sets come with a Supplemental Recovery Disc. If there is a Supplemental Recovery Disc, it will be clearly marked as such.
8. When all of the data has been copied from the last disc in the set and has been processed, remove the external CD/DVD drive and restart the computer. Follow the instructions on the screen to finish the recovery.
Resetting your computer
If your computer does not perform well,you might consider resetting your computer. In the resetting process, you can choose to keep your files or remove them, and then reinstall the Windows operating system.
To reset your computer, do the following:
Note: The graphical user interface (GUI) items of the operating system might change without notice.
1. Open the Start menu and then click Settings. If Settings is not displayed, click All apps to display all programs, and then click Settings > Update & security > Recovery.
2. In the Reset this PC section, click Get started.
3. Follow the instructions on the screen to reset your computer.

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