Lenovo IdeaPad - U550
To verify a symptom, follow the
steps below:
1. Turn off the computer.
2. Remove the battery pack.
3. Connect the AC adapter.
4. Make sure that power is supplied when you turn on the computer.
5. Turn off the computer.
6. Disconnect the AC adapter and install the charged battery pack.
7. Make sure 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 adapter”
“Checking operational charging”
“Checking the battery pack”
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.
If the computer does not charge during operation, go to “Checking operational charging”.
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:
1. Turn off the computer.
2. Remove the battery pack.
3. Connect the AC adapter.
4. Make sure that power is supplied when you turn on the computer.
5. Turn off the computer.
6. Disconnect the AC adapter and install the charged battery pack.
7. Make sure 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 adapter”
“Checking operational charging”
“Checking the battery pack”
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.
If the computer does not charge during operation, go to “Checking operational charging”.
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.
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 does not light on, 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 still does not light on, replace the system board.Then reinstall the battery pack. If it is still not charged, go to the next section.
Checking the battery pack
Battery charging does not start until the Power Meter shows that less than 95% of the total power remains; under this condition the battery pack can charge to 100% of its capacity. This protects the battery pack from being overcharged or from having a shortened life.
To check your battery, move your cursor to the Power Meter icon in the icon tray of the Windows taskbar and wait for a moment (but do not click it), and the percentage of battery power remaining is displayed. To get detailed information about the battery, double-click the Power Meter icon.
Note: If the battery pack becomes hot, it may not be able to be charged. Remove it from the computer and leave it at room temperature for a while. After it cools down, reinstall and recharge it.
If the charge indicator still does not light on, replace the system board.Then reinstall the battery pack. If it is still not charged, go to the next section.
Checking the battery pack
Battery charging does not start until the Power Meter shows that less than 95% of the total power remains; under this condition the battery pack can charge to 100% of its capacity. This protects the battery pack from being overcharged or from having a shortened life.
To check your battery, move your cursor to the Power Meter icon in the icon tray of the Windows taskbar and wait for a moment (but do not click it), and the percentage of battery power remaining is displayed. To get detailed information about the battery, double-click the Power Meter icon.
Note: If the battery pack becomes hot, it may not be able to be charged. Remove it from the computer and leave it at room temperature for a while. After it cools down, reinstall and recharge it.
DISASSEMBLING PROCEDURE: How to
remove Battery pack
Remove ten screws 1 and two
screws 2.
Open the back cover in the
direction shown by arrow 3.
How to remove Hard disk
drive
Remove the frame fixing screws 1.
Pull the tab in the direction shown by arrow 2.
Hold the SATA receptacle
connector with one hand and pull the hard disk drive (secured in the metal
frame) in the direction shown below to detach the connector.
