Troubleshooting Chart For Controller - Motorola GP344 Detailed Service Manual

Audio at
INT
AudioPA
AUDIO
NO
(U420)
J403 Audio
at Pin 2 &
(U447)
Pin 3
YES
Audio from Pin 41
Check Spk. Flex
ASFIC, U404?
Connection
Check NO
Audio at
U301
Pin 2
LV ZIF
U404?
Check
ASFIC U404
EXT
PTT
Radio could
not PTT
externally
OPT_SEL_1 &
OPT_SEL_2
Pin 8 & 9
EXT
SPKR
J403 Pin 9
NO
low? Pin 8
high?
YES
NO
ASFIC U404
Pin 14 & 15
high?
YES
Check
U420 Audio PA
PTT
Press PTT. Red
LED does not
light up
YES
input
PTT U409
Pin 53
Check
low?
Audio PA
(U420)
YES
NO
Press PTT
Q502-2
NO
High?
No
Check
Q502-2
voltage
YES
YES
LED should
light up
J403
NO
Check
Accessories
low?
YES
U409
YES
Pin 52, 6
low?
Check
NO
See FGU
Accessories
Troubleshoot-
ing chart
Check
U404
Figure 2-6 Troubleshooting Chart for Controller
MCU Check
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
YES Not able to pro-
MCU, check SPI
gram RF Board
clock, SPI data,
ICs
and RF IC select
NO
Replace
Speaker
YES
NO
Read Radio
OK?
YES
Reprogram the
NO
See FGU
Troubleshooting
7.5V at
NO
NO
Pin 3/5 U247?
4/3.3V at Pin 1
U248
YES
U247/U248
NO Check any short
to SWB+,
Vdda or Vddd
2-7
Check
Setup
correct data.
Check
Q400
Replace