Motorola HT Series Service Manual page 98


MCU Check.
Power Up YES Not able to pro-
Alert Tone gram RF Board
ICs.
OK?
NO
NO
Replace Speaker.
Speaker
OK?
YES
YES
U409 EXTAL=
Read Radio OK?
7.3728 MHz?
NO
NO
U201 Pin 19
16.8 MHz.
YES
NO
7.5V at
5V at U202? Pin 3/5 U202?
3.3V at U203?
4/3.3V at Pin 1
U203.
YES
Check any short to
NO
U409 Reset
SWB+,
Pin 94 High?
Vdda or Vddd.
YES
MCU is OK.
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Before replacing MCU,
check SPI clock, SPI
data, and RF IC
select.
NO
Check
Setup.
YES
Reprogram the
correct data.
See FGU
Troubleshooting.
NO
Check Q400.
YES
Replace
U202/U203.