Power-On Failure - Lenovo A516 Service Manual

Repair Manual of Lenovo A516 Mobile Phone

3.7 Power-on failure

Failed to Power-on
Check whether the power key FPC is
assembled well , reassembling the
power FPC ?
Power on the phone on separate main
board , whether there is high current?
Check whether the 26MHz on
U2106 is normal? Whether there is
26MHz signal on R2116?
Check whether X1303， C1319，
C1324 are well welded
Check whether the main power supply of U1301
is normal?
（VCORE,VAPROC,VDD18,VTCXO,VDD25_
VA1,VDD28,VMC, etc.）
Replace the main chip U1101
N
N
N
Y
N
Y
Y
23
Y
Re-weld
The main board is damaged;
Y
replace the main board and check
the failure board step by step
Re-weld and recheck
Re-weld and recheck
N
Re-weld
replace device
U1301
recheck
or
to