Motorola MTM800 - Controller Troubleshooting (Sheet 2)

TROUBLESHOOTING CHARTS: 450-470MHz 9.1 - 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
controller
U1100
16.8MHz
signal at TP5331
?
No
Yes
Before replacing U5331 check
components between collector
Q0100 and U5331 pin 19, check
components between Y5363 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 Y5363
pin 3
?
Yes
Check
transistor
stage
Q5351
No
2.8V DC
at C0324
?
Yes
No
9.3V DC
at C0308
?
Yes
No
Before replacing
Y5363 check R5364
No
9.3V DC
at U5322 pin 5
?
No
9.3V DC supply failure!
Go to DC Supply Chart
Yes
Replace
U5322
A
Replace
U0307
From Sheet 1
6866539D31.book Page 5 Tuesday, March 20, 2007 6:32 PM