Sony UP-960 Service Manual page 48

5-2. PRINT IS TOO DARK OR TOO LIGHT
(approx. 5.7 V) at pin 4 of IC6
on MA-91 board output when
"CONTRAST" is set as
center value?
(approx. 1.4 V) at pin 6 of IC6
on MA-91 board output when
"BRIGHT" is set as
center value?
(approx. 1.5 to 2.5 V)
available at pin 78 of IC505 on
MA-91 board when head
is at the normal
temperature?
Are required
voltages available at each
terminal, 3 V at 19 pin of IC6 and
IC7 on MA-91 board, and
1 V at 23 pin of
Is density of stair step
printed in test mode properly?
5-2
START
Is voltage
NO
YES
Is voltage
NO
YES
Is voltage
NO
YES
NO
the IC's?
YES
NO
YES
IC203 and IC201 or
peripheral circuit of Q16 on
MA-91 board are defective.
Peripheral circuits IC203 and
IC201 or Q15 and Q17 on
MA-91 board are defective.
Peripheral circuit IC404 and
pins 15 and 16 of CN202 line
on MA-91 board, or the
thermistor in the head are
defective.
Peripheral circuit Q21 on
MA-91 board is defective.
The head voltage or CN202
on MA-91 board is defective.
The data buses of IC7 and
IC603 or peripheral circuit
IC2 on MA-91 board are
defective.
UP-960(UC)
UP-960CE(CE)