Chapter 6 Uhf Band 2 Troubleshooting Charts; Troubleshooting Flow Chart For Controller - Motorola HT Series Detailed Service Manual

UHF Band 2 Troubleshooting Charts: Troubleshooting Flow Chart for Controller

Chapter 6 UHF Band 2 Troubleshooting Charts

6.1

Troubleshooting Flow Chart for Controller

INT
AUDIO
NO
AudioPA
J403 Audio
at Pin 2 &
Pin 3
YES
Audio from Pin 41
Check Spk. Flex
ASFIC, U404?
Connection
Check NO
Audio at
U301
IF IC
ASFIC U404
EXT
PTT
Radio could
not PTT
externally
OPT_SEL_1 &
OPT_SEL_2
Pin 8 & 9
EXT
SPKR
NO
J403 Pin 9 low?
Pin 8 high?
YES
NO
ASFIC U404
Pin 14 & 15
high?
YES
Check
U420 Audio PA
FMR-2045A-2
PTT
Press PTT. Red
LED does not
light up
Audio at
YES
(U420)
input
PTT U409
(U447)
Pin 53
Check
low?
Audio PA
(U420)
YES
NO
Press PTT
Q502-2
NO
High?
No
Check
Pin 2
Q502-2
U404?
voltage
YES
Check
YES
LED should
light up
J403
NO
Check
Accessories
low?
U409
YES
YES
Pin 52, 6
low?
Check
NO
See FGU
Accessories
Troubleshoot-
ing chart
Check
U404
MCU Check
YES
Power Up
Alert Tone
OK?
NO
NO
Speaker
Check
OK?
PB504
YES
YES
U409 EXTAL=
7.3728 MHz?
NO
LED
Q502,R501
OK?
U201 Pin 19
16.8 MHz
No
Replace
YES
Faulty
Component
5V at U247?
3.3V at U248?
YES
Check
MCU
U409 Reset Pin
94 High?
YES
MCU is OK
Before replacing
Not able to pro-
MCU, check SPI
gram RF Board
clock, SPI data,
ICs
and RF IC select
NO
Replace
Speaker
YES
NO
Check
Read Radio
Setup
OK?
Reprogram the
YES
correct data.
NO
See FGU
Troubleshooting
7.5V at
NO
NO
Check
Pin 3/5 U247?
Q400
4/3.3V at Pin 1
U248
YES
Replace
U247/U248
NO Check any short
to SWB+,
Vdda or Vddd
December 26, 2003
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