Apc - Lenovo A516 Service Manual

Repair Manual of Lenovo A516 Mobile Phone

4.2.3 APC

Fault 1
⚫
Fault: APC calibration Fail.
⚫
Cause: RF test cable is not connected well during calibration; PA is oppositely pasted; PA
and peripheral circuit are in cold solder joint; The patch of RF input circuit of PA is deviated
with short-circuit shield box.
⚫
Shooting:
GSM frequency
fails?
Re-weld
PA input are
C2102 ,R2102
Y
welded with
disconnection?
Whether PA is in
Weld PA
U2102
cold solder joint?
⚫
Notes:Remeber to recalibrate after replacing compements; the problem analysis of PCS
TX APC is the same as DCS.
N
Check calibration report to
see whether each frequency
N
bands fail?
Y
DCS1800/PCS190
Y
0 frequency fail
N
PA input
N
C2101 ,R2102 are
welded with
disconnection？
Whether
PA(U2102) is in
cold solder joint?
PCL calibration Fail
Y
Replace
Y
components
Replace PA
29
Y
Check whether RF
Y
cable and fixtures are
well connected?
Whether RF connector
N
CON2101、
R2115,C2131,C2113,C2
214 are in cold solder
joint?
Whether PA（U2102）is
in cold solder joint?
N
Reconnect
and calibrate
Y
Re-weld
Y
Re-weld
U2102