Lenovo V370: Power
system checkout
To verify a symptom, do the following:
1. Turn off the computer.
2. Remove the battery pack.
3. Connect the ac adapter.
4. Check 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. 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 backup battery”
Checking the ac power adapter
If you computer fails only when the ac power adapter is used, use the instructions in this topic.
If the power problem occurs only when the docking station or the port replicator is used, replace the docking station or the port replicator.
If the power-on indicator does not turn on, check the power cord of the ac power adapter for correct continuity and installation
1. Turn off the computer.
2. Remove the battery pack.
3. Connect the ac adapter.
4. Check 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. 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 backup battery”
Checking the ac power adapter
If you computer fails only when the ac power adapter is used, use the instructions in this topic.
If the power problem occurs only when the docking station or the port replicator is used, replace the docking station or the port replicator.
If the power-on indicator does not turn on, check the power cord of the ac power adapter for correct continuity and installation
If
the computer does not charge during operation, go to . To check the ac adapter,
do the following:
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 illustration:
2. Measure the output voltage at the plug of the ac 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 adapter.
4. If the voltage is acceptable, 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 correctly during operation, do the following:
Note: Before you begin, install a discharged battery pack or a battery pack that has less than 50% of the total power remaining in the computer.
1. If the battery status indicator does not turn on, remove the battery pack and let it return to room temperature.
2. Reinstall the battery pack.
3. If the indicator still does not turn on, replace the battery pack.
Checking the battery pack
The battery status icon in the Windows notification area displays the percentage of battery power remaining. To check for detailed battery status information, do the following:
For 7: Open the Power Manager program and click the Battery tab.
For 8: Open the Lenovo Support program and click Battery Health, or 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. Turn off the computer and disconnect the ac power adapter.
2. Remove the battery pack and measure the voltage between battery terminals 1 (+) and 7 (-). The correct voltage are shown in the following table.
4. If the voltage is acceptable, 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 correctly during operation, do the following:
Note: Before you begin, install a discharged battery pack or a battery pack that has less than 50% of the total power remaining in the computer.
1. If the battery status indicator does not turn on, remove the battery pack and let it return to room temperature.
2. Reinstall the battery pack.
3. If the indicator still does not turn on, replace the battery pack.
Checking the battery pack
The battery status icon in the Windows notification area displays the percentage of battery power remaining. To check for detailed battery status information, do the following:
For 7: Open the Power Manager program and click the Battery tab.
For 8: Open the Lenovo Support program and click Battery Health, or 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. Turn off the computer and disconnect the ac power adapter.
2. Remove the battery pack and measure the voltage between battery terminals 1 (+) and 7 (-). The correct voltage are shown in the following table.
3.
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.
4.
Depending on the voltage that you measure, do one of the following:
If the voltage is less than +11.0 V dc, recharge the battery pack. If the voltage is still less than +11.0 V dc after recharging, replace the battery pack.
If the voltage is more than +11.0 V dc, discharge the battery pack until the voltage becomes less than +11.0 V dc and then recharge the battery pack. If the voltage still is less than +11.0 V dc after recharging, replace the battery pack.
Note: Recharging will take at least three hours, even if the battery status indicator does not turn on.
5. Replace the system board if the new battery pack is not charged.
Checking the backup battery
Do the following:
If the voltage is less than +11.0 V dc, recharge the battery pack. If the voltage is still less than +11.0 V dc after recharging, replace the battery pack.
If the voltage is more than +11.0 V dc, discharge the battery pack until the voltage becomes less than +11.0 V dc and then recharge the battery pack. If the voltage still is less than +11.0 V dc after recharging, replace the battery pack.
Note: Recharging will take at least three hours, even if the battery status indicator does not turn on.
5. Replace the system board if the new battery pack is not charged.
Checking the backup battery
Do the following:
1.
Power off the computer, and unplug the ac adapter from it.
2. Turn the computer upside down.
3. Remove the battery pack
4. Remove the backup battery
5. Measure the voltage of the backup battery. See the following illustration.
2. Turn the computer upside down.
3. Remove the battery pack
4. Remove the backup battery
5. Measure the voltage of the backup battery. See the following illustration.
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.
If the backup battery discharges quickly after replacement, replace the system board.
