Print Density Is Too High Or Too Low - Sony UP-D898MD Service Manual

2-2-6. Print density is too high or too low

Print density is too high or too low.
Is the voltage at pins 1 and 2 of
CN101 on the MA-195 board
changed to less than 1 V during
standby and to 25 V or more
during printing?
Yes
Is the voltage at pin 29
(THERMISTER) of CN701 on the
MA-195 board approx. 2.0 V to
2.4 V when the temperature is
25 C?
Yes
Is the density of sample print
normal?
No
Is the head voltage setting for the
thermal head resistance value
appropriate?
Yes
Is the voltage at pins 1 and 2 (VH)
of CN101 on the MA-195 board
set to the head voltage setting
value during printing?
Yes
Is the voltage at pin 3 (VCONT)
of CN101 on the MA-195 board
set to the voltage corresponding to
the head voltage setting value
during printing?
Yes
Relational expression: VH = 6
Replace the MA-195 board.
(Refer to Section 3-1.)
UP-D898MD/X898MD
FFC: Flexible flat cable
No
Replace the MA-195 board.
(Refer to Section 3-1.)
Is the pin 30 FFC connecting
No
CN701 on the MA-195 board and
thermal head connected correctly?
Replace the thermal head.
(Refer to Section 3-7.)
Again, is the voltage at pin 29
(THERMISTER) of CN701 on the
MA-195 board or CL712 (THERM)
approx. 2.0 V to 2.4 V when the
temperature is 25 C?
Yes
Replace the MA-195 board.
(Refer to Section 3-1.)
No
Set the thermal head voltage
value appropriately.
No
Replace the MA-195 board.
(Refer to Section 3-1.)
No
Replace the switching regulator.
(Refer to Section 3-5.)
VCONT + 25 V (VCONT
No
Yes
Yes
No
0.8 V, VH tolerance: 3%)
Check the connection of FFC.
If the symptom persists, replace
FFC. (Refer to Section 5.)
Normal
Replace the MA-195 board.
(Refer to Section 3-1.)
2-9 (E)