Yaesu FT-901DM Maintenance Service Manual page 97

SERVICING
COMMON CIRCUITS
Problem Condition Probable Cause(s)
(1) Counter circuit (a) Digital display does * Defective Qro25
not work * 5V line in Counter Unit grounded
* Defective display LED
* Defective Qro17, Qzo19 5 Qzo22 » Qaoz3
* Defective R2932 —R29s2
If no VFO signal and VFO LED is not
lighted, check SELECT switch and
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