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lunedµ 20 dicembre 1999
note: all the signal & voltage present
in this procedure has to be clear and
at correct level ; compare them with a
good pcb
Supply phone using
Ext_B+ (~4.5V) on Butt-plug
and check if
phone power up correctly
set power supply
generator to 4 Vcc and
check if phone power up
Make a short on W.D. line on R941 side ( near
C913 ) AND CHECK FOLLOWING
FOLTAGES:
-V_BOOST = 5,6 V on C913
-V1 =5V on C906
-V2 =2,8 V on C939
(R905)-V3 = 1,8 V on C909
-SR_VCC = 2,8 V on R722
-VRef =2,8 V on C919
SEE TIMING SEQUENCE on Pag. 16 , 17.
Does 26 MHz
NOTE: check if any components mentioned is correctly
positioned , has not dry joint and is not damaged . If all is ok
replace it . If problem is still the same send BOARD IN htc.
NO
correctly
NO
YES
clock is
present on
L220 ?
YES
Go to " 2 "
on pag. 03
- MOTOROLA CONFIDENTIAL PROPRIETARY -
Dual band Taishan level 3 debug rev 1.0
YES
Check Ext_B+ from J600
YES
Check CR903, Q905
and NOTE1 or faulty.
For V_BOOST issue check L901 ,
C980 , C970 , C981 , CR 902 ,
C913 for other voltages issues
NO
check any line for short or different
resistence ( compare with a good
Check Y200 , C220 , L220 for
missing , dry joint or faulty , check
also for " VRef " voltage presence
NO
= 2,8 V on C213 , if not ok check
line between C919 & C213.
Finally check on C215 for "RF_V2
" voltage = 2,8 V presence and for
" RF_V1 "voltage = 2,8 V on
NO
POWER
UP
to CR903 if OK
one ).
C217.
Page 3
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