Sony UDA-1 Service Manual page 17

2. When protector happened
START
Check that the harness is
Check that the all
NG
correctly inserted in CN215 on
input indicator
the AMP board and CN303 on
LEDs are not
the DIGITAL board.
blinking (blinking is
protector).
Check that thermistor voltage
of the following pin is 0.5 V to
2.0 V.
AMP board: JL201 or
CN215 pin 9 (TEMP1)
Check that DC off set voltage
of the following pin is just
about 0 V.
AMP board: CL215
Check that the heat sink and
IC350 and IC351 on the AMP
board is touches completely.
Check that the heat sink and
chassis touches completely.
Check that the harness is
correctly inserted in CN191
(for fan (M1)) on the DCDC
board.
Exchange in order of the
AMP board, DIGITAL board,
T001 (main power transformer).
3. When USB FRONT indicator LED is blinked
START
Check that the Check that the USB device
NG
USB FRONT that is not compatible with front
indicator LED is USB jack is not connected.
not blinking.
Repair the harness which
connects DIGITAL board
(CN501) and F-USB board
(CN802).
NG
Repair the harness.
OK
Check the following parts and
NG
the surrounding circuit.
AMP board: TH200
OK
Check the following parts and
NG
the surrounding circuit.
AMP board:
Q202, Q203, Q205, Q206
OK
NG The screw is fastened so that
a heat sink may be strongly
touched to IC350 and IC351
on the AMP board.
OK
NG The screw is fastened so that
a heat sink may be strongly
touched to chassis.
OK
NG
Reinsert the harness.
OK
NG
Disconnect the USB device.
OK
NG
Exchange the F-USB board.
NG
Exchange the TH200 on the
AMP board.
NG
Exchange the AMP board.
NG
Exchange the DIGITAL board.
UDA-1
17