Trouble Shooting - Lenovo L2021 Wide Service Manual

Lenovo Service Manual

9.3 Trouble Shooting

Main Board---
No Power
No power
Press power key and look if
the picture is normal
NG
Please reinsert and make sure the AC
100-240V is normal ?
OK
Check 5V-CN201, 3.3V-U201-2;
Q401,1.8V-Q501,Panel-Vcc-Q601
OK
Check X401 waveform
OK
Replace U401/U501
NG
Reinsert or check the power section
NG
Check&replace CN201, U201, Q401,
Q501,Q502, Q601,Q602
NG
Replace X401
37
Check flow chart
For the no power
L2021W