Friday, May 06, 2016

Lenovo ThinkPad S440 – How to test the battery pack - How to test the AC adapter – Testing Backup battery – Laptop repair and Service

Category: Laptop repair and Servcie 

Contents of this article

  • How to Remove the HDD Password
  • How to test the AC adapter
  • How to test the Back up battery 

Lenovo ThinkPad S440

Power system checkout
To verify a symptom, do the following:
1. Connect the ac power adapter and turn on the computer.
2. Check that power is supplied when you turn on the computer.
3. Insert a straightened paper clip into the emergency reset hole to reset the computer. Confirm the system is still powered on.
4. Turn off the computer and disconnect the ac power adapter.
5. Check that the battery pack supplies power when you turn on the computer.
If you suspect a power problem, see the appropriate one of the following power supply checkouts:
“Checking the ac power adapter”
“Checking operational charging”
“Checking the battery pack”
“Checking the coin-cell battery”
Checking the ac power adapter
If your computer fails only when the ac power adapter is used, use the following instructions.
If the power problem occurs only when the dock is used, replace the dock.
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 across 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 battery pack charges correctly during operation, do the following:
1. Discharge the battery pack until the remaining battery power is less than 50%.
2. Connect the computer to ac power to charge the battery pack. If the battery status icon in the Windows notification area indicates that the batteries are not charging, disable the built-in battery in the BIOS, remove the battery pack, and let them return to room temperature.
3. Reinstall the battery pack. If the batteries are still not charging, replace the battery pack.
Checking the battery pack
To check for detailed battery status information, do the following:
For 7: Open the Power Manager program and click the Battery tab.
For 8 and 8.1: Open the Lenovo Settings program and click OK.
Checking the coin-cell battery
To check the backup battery, do the following:
1. Disable the built-in battery.
2. Remove the backup battery
3. Measure the voltage of the backup battery. See the following figure.
If the voltage is correct, replace the system board.
If the voltage is not correct, replace the backup battery.
If the backup battery discharges quickly after replacement, replace the system board.
How to remove the hard disk password
To remove a user HDP that has been forgotten, when the master HDP are known, do the following:
1. Turn on the computer.
2. When the ThinkPad logo comes up, immediately press F1 to enter ThinkPad Setup.
3. Select Security, using the cursor directional keys to move down the menu.
4. Select Password.
5. Select Hard-disk x password, where x is the letter of the hard disk drive. A pop-up window opens.
6. Select Master HDP.
7. Type the current master HDP in the Enter Current Password field. then leave the Enter New Password field blank, and press Enter twice.
8. Press F10 to save changes and exit the ThinkPad Setup program.
9. Select Yes in the Setup Notice window. Both user HDP and master HDP will have been removed.