Lenovo A859 Service Manual - Page 21

Browse online or download pdf Service Manual for Cell Phone Lenovo A859. Lenovo A859 36 pages.
Also for Lenovo A859: Important Product Information Manual (23 pages), Quick Start Manual (6 pages), Quick Start Manual (13 pages), Quick Start Manual (33 pages)

Print Page
Lenovo A859 Service Manual
Repair Manual of Lenovo S920 Mobile Phone

Power-on failure

Failed to Power-on
Check whether the power key FPC is
assembled well , reassembling the
power FPC ?
N
Power on the phone on separate main
board , whether there is high current?
N
Check whether the 26MHz on
U2104 is normal?
Y
Check whether X1301, C1336
and C1337are well welded
Y
Check whether the main power supply of U1302
is normal?
（VCORE,VAPROC,VDD18,VTCXO,VDD25_
VA1,VDD28,VMC, etc.）
Y
Replace the main chip U1201
Y
Re-weld
The main board is damaged;
Y
replace the main board and check
the failure board step by step
N
Re-weld and recheck
N
Re-weld and recheck
N
Re-weld
or
replace
device
U1302
to
recheck
21