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Customer Care Europe, Middle East & Africa
SCCE Training Group
Phone does not switch on
The first thing you should do in this case is to check the current consumption of the phone:
Off-state current normally varies between 0.1 mA and 0.6 mA, sleep mode current varies between 0.6 mA and 4 mA while
call mode current varies between 100 mA (lowest TX-power level, lights off) and 550 mA (highest TX-power level, lights on).
In case the current consumption increases to more than 0.5 A immediately after connecting the phone to the service-battery or
immediately after pressing the power button continue with chapter "Low standby/operation mode time".
If current consumption is lower than 0.5 A, check VB 3.6 VDC at C227/228.
If voltage is not ok, check if contact pads for battery connector on PCB are clean. Also check solderings
and resistance of L513 and L201.
If VB 3.6 VDC at C227/228 is ok, check whether voltage at R402 drops from 4 VDC to 0 V while pressing the power switch.
If voltage at R402 is 4 VDC but does not low down to 0 V when power switch is pressed, usually the switch S419
itself is defect.
In case that no or too low voltage is measurable at R402, check POWERONX-line for interruption.
Therefore check solderings and resistance of R402 and R224. It also can be necessary to change CCONT N201
Check whether 32.768 kHz oscillator is working:
Figure 3-1
Amplitude of 32.768 kHz at C220 is 3 Vpp. If signal is not measurable check periphery of B200 as
R211/212/214 and C229/230,.Change crystal B200 if necessary. If this does not solve the problem
change CCONT N201. Remember to run energy management calibration after changing CCONT N201!
If all the above mentioned works the output voltage lines of CCONT must rise to their supposed values.
Check VBB 2.8 VDC at C209/211, VXO 2.8 VDC at C243 and VCORE 1.7 VDC at both sides of L200.
If only one of these voltages is not measurable, check lines for shorts to ground.
Resistance of VBB-line to GND normally is around 90 k? , resistance of VXO-line is ~45 k? while resistance of
VCORE-line is ~180 k? . Check parts in corresponding line if resistance is too low.
In case that one of the mentioned voltages is not measurable even tough resistance of the line is ok it is
necessary to change the CCONT. Remember to run energy management calibration after changing CCONT N201!
If both VBB, VXO and VCORE are ok, check 13 MHz reference-clock at C303:
Figure 3-2
© NMP 2002
CONFIDENTIAL
NHM—2/5/6
3410
Date 20.11.2002
Checked by:
Customer Care E&A
18 (44)
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SCCE Training Group
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