Nokia RM-12 Troubleshooting Instructions page 52

CCS Technical Documentation
APE
Power on
Supply voltage
drops(or current YES
is large)?
NO
Measure VBAT
from input filters
C4200, C4209, NO
L4203(both sides)
OK?
YES
Check
V28(~2.8V), NO
OK?
YES
Visit APE reset
troubleshooting
Check SYNC/
MODE from
R4202 (both NO
sides), High
(>2V)?
YES
Check
V15(~1.57V), NO V15 > 1.62V ?
OK?
YES
Check V18
NO V18 >1.89V ?
(~1.8V), OK?
enable (VIO),
YES
high (1.8V)?
END
50
Note! OMAP, UEM and UPP are unchangeable.
Short circuit in
VBAT line
Failure on VBAT
line, check
components and
connectors
Check Change V28
enable(VIO), YES regulator(N4200)
high (1.8V)? and retest, OK?
NO
Shortcut in V28
UEM fault
R4200 or
Faulty V1600 or
R4202, change
and retest
Check enable
NO (VFLASH1),
high (2.8V)?
NO
UEM fault
No
Check
Check
ref. voltage
YES
at C4211,
1.35V ?
NO
NO
Ref.
voltage found
UEM fault NO
at either end of
L4200 ?
COMPANY CONFIDENTIAL
Copyright © 2004 Nokia. All Rights Reserved.
NO
line
YES
Check
voltage at L4201
YES
(both sides low),
~0V ?
NO
Change coil and
retest V15
YES
Check
voltage at L4202
YES
(both sides low),
<1V ?
NO
Change filter
YES
(L4200)
RM-12
Change SMPS
YES chip(N4201) and
retest, OK?
NO
Shortcut in V15
line
Change SMPS
YES chip (N4202)
and retest, OK?
NO
Change coil and Shortcut in
retest V18 V18 line
Issue 1 11/2004