Motorola MTM700

TROUBLESHOOTING CHARTS (800MHz) MTM700 Mobile Radio / Detailed Service Manual 9.2 - 5
Controller Troubleshooting (Sheet 2)
32.768kHz
signal at U0100 pin 18
?
Yes
16.8MHz
signal at collector of
Q0100
?
No
Yes
No
9.3V DC supply failure!
Go to DC Supply Chart
Measure the 16.8MHz
and the 32.768kHz
signals with a scope
Replace MCM
board, flash
firmware and
codeplug
16.8MHz
signal at Q5351
collector
?
No
Yes
Before replacing U5331 check
components between collector
Q0100 and U5331 pin 19, check
components between Y5362 and
U5331 pin 23.
5V DC
at U5322 pin 4
?
Yes
32.768kHz
signal at U0100 pin 3
?
No
Replace
Y0101
Before replacing
U0100 check
associated
components
Yes
16.8MHz
signal at Y5362 pin 3
?
Yes
Check
transistor
stage
Q5351
No
3V DC
at U5321 pin 5
?
Yes
Replace
Y5362
No
9.3V DC
at U5321 pin 1
?
Yes
No
Before replacing
U5321 check R5321
No
9.3V DC
at U5322 pin 5
?
No
9.3V DC supply failure!
Go to DC Supply Chart
Yes
Replace
U5322
A
From Sheet 1
ZWG0130961-O