Single Tone Failure - Motorola VRS750 Service Manual

72

SINGLE TONE FAILURE

START
Verify that the VRS750
dip switches are set to
normal operation.
Verify that J30-20
(boot control) is
~3.3VDC.
Does
TP105 pulse ~5VDC
when the volume button
is pressed?
Yes
Does J30-21
pulse to ~0VDC when
the volume button is
pressed?
Yes
Is there
continuity between
J30-21 and J20-9 on the
flex cable?
Yes
Check and/or
replace the
transceiver.
Chart 9—Single Tone Failure
No
Check the mobile
to VRS cable.
Check and/or
No
replace U103 and
Q103.
No
Replace the flex
cable.