Lenovo 1304XF8, T20x2-1, K1 manual Power system checkout, Checking the AC adapter, General checkout

General checkout

Power system checkout

If you suspect a power problem, see the appropriate one of the following power supply checkouts:

•• “Checking the AC adapter ” on page 21

•• “Checking the battery pack ” on page 22

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.

To check the AC adapter, follow the steps below:

1.Unplug the AC adapter cable from the tablet.

2.Measure the output voltage at the plug of the AC adapter cable. See the following figure:

1

2

Pin Voltage (V DC)

1+20

20

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.

•• If the problem continues, go to “Lenovo IdeaPad Tablet K1” on page 27. Note: Noise from the AC adapter does not always indicate a defect.

21