Power System Checkout; Checking The Ac Power Adapter - Lenovo ThinkPad 11e Chromebook Hardware Maintenance Manual

The following are not covered under warranty:
• LCD panel cracked from the application of excessive force or from being dropped
• Scratched (cosmetic) parts
• Distortion, deformation, or discoloration of the cosmetic parts
• Plastic parts, latches, pins, or connectors that have been cracked or broken by excessive force
• Damage caused by liquid spilled into the system
• Damage caused by the improper insertion of a PC card or the installation of an incompatible card
• Fuses blown by attachment of a nonsupported device
• Forgotten computer password (making the computer unusable)
• Sticky keys caused by spilling a liquid onto the keyboard
• Use of an incorrect ac power adapter on laptop products
The following symptoms might indicate damage caused by nonwarranted activities:
• Missing parts might be a symptom of unauthorized service or modification.

Power system checkout

To verify if a battery and an 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. Turn off the computer.
5. Disconnect the ac 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" on page 28
• "Checking the battery and operational charging" on page 29

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.
• If the computer does not charge during operation, go to "Checking the battery and operational charging"
on page 29.
To check the ac power adapter, do the following:
1. Disconnect 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:
3
2
1
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.
28
Hardware Maintenance Manual
(20V)
Pin
Voltage (V dc)
1 +20
2 0
3 Ground