User Guide

RH-23 Company confidential
CCS Technical Documentation
Page 56 Nokia Corporation. Issue 1 03/2004
Figure 49: FM-Radio failure troubleshooting
Set phone into LOCAL
mode. Start FM-radio.
Does the radio
start?
OK
,
RETEST
Yes
Check C374, C375,
R357, R358 and
measure 32kHz clk
signal from J357,
retest starting.
Start OK?
No
Measure Audio signal
from C162 and C163.
Is it 1kHz 0.5-0.8Vpp?
Check R164, R165,
R166, R167, L103,
L104. Measure signal
from J103 and J104.
Is it 0.015-0.3Vpp?
Change N356.
Start OK now?
Yes
Set Radio and RF generator
to 87.5 and 108.0MHz.
Measure Audio from
C162 and C103. Are both
cases 1kHz 0.5-0.8Vpp?
Change Radio
module
Change
Audio
Amplifier
(N150)
No
Yes
No
Check V356, V357,
L356, L357, C357,
C358, C362, R359,
R360. Test again
with 87.5 and
108.0MHz.
Measure audio
from C162 and
C163. Both OK?
Connect RF-test signal (note).
Set radio channel to 98.0MHz.
Set radio volume to max.
No
Measure
voltages from
pins 7 and 34.
Is it ~2.7V?
Retest starting.
Start OK now?
No
Check N356
solder on pins
5-9,11-
13,17,33-37.
Start now OK?
No
Yes
Chan
g
e UPP
(
D400
)
No
No
Yes Yes
No
Check C107,C108,
C109, C117, L105,
C367, C378, C379,
L358. Measure signal
from C162, C163.
Is it 1kHz 0.5-0.8V
pp
?
No
Check R359, R360,
V356, V357, L356,
L357, C357, C358,
C352. Measure signal
from R105, R105, OK?
OK
,
RETEST
No
Change N356.
Measure signal from
R105 and R106.
Is it OK?
No
Ye
s
Yes
Yes
Yes
Ye
s
Yes
No
Change V356 and V357
BOTH!
Retest with 87.5 and
108.0MHz. Measure audio
from C162 and C163.
Both OK?
Yes
No
Figure 22: FM-Radio failure troubleshooting