Phone Switch It Self Off - Nokia 3210 Service & Repair Manual

Phone switch it self off

Check if this happens
only with 5V SIM-cards
and if the phone works
probably with 3V SIM's
not oK
Check the 5V
supply voltage on
C136 with an
oscilloscope
not oK
Change C131 if the
noise is higher than
350mVpp
C136 10μF/10V
Check, if the handset doesn't switch off with 3V SIM-Cards
Check that the 5V VSIM voltage on the capacitor C136 is approximately 4,8V-5,2V with
maximal 350mVpp noise overlap (view the diagram below)
version 1.0 / 05.11.1999
CONFIDENTIAL
Phone intermittend switches off
Check X101 and X102,
oK
if poor soldered, bent
or soiled
oK
Check amplitude of
32,768KHz square
wave at C149
oK
Check amplitude of
13MHz
RF Clk C301 (2,8Vpp)
oK
Check VBB 2,8V DC
on
C117
Service & Analysis Center Europe
Resolder, change or
not oK
clean the connector
Change or check
soldering of B100,
not oK
C147, C148, C153,
N100
Change or check
not oK soldering of G701,
V702...
Change or check
not oK
soldering of N100,
C117
Training Team
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