Roadstar DVR-9100, Service Manual

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23
TROUBLE SHOOTING
B. Front panel buttons
Front panel
buttons
Remove F/W (U25) and
replace it with a working
F/W, check if the machine
will function normally.
Replace main board
Remove the top cover, remove
the panel; check if there’s any
signal output on pin15, 16 of U1
on the front board(also check for
bad soldering)
Check U34 and any
components nearby for
bad soldering, open/short
circuit, damage, etc.
Check SW1~SW7 and any
components nearby for bad
soldering, open/short circuit,
damage, etc.
Check the 12pin cable that
connects the front board with the
main board, check if the cable is
properly connected.
Check the 12pin cable that
connects the front board
with the main board, check
if the cable is properly
connected.
Replace front board
Use the oscillator or multimeter to
check if the voltage between p10
and GND of JP6 on the main
board –27V and also check if the
voltage between pin2 and GND 5V
OK
Replace power board
No
Yes
No
Yes
No
Yes