System Does Not Start - Sony PVM-A250 Service Manual

4. State in which D6228, D6407, D6408, and D6229 were turned on
Abnormality is found in an AC voltage or AC detection circuit (AC OFF DET circuit). Confirm the item
below using a tester.
. Confirm whether an AC input voltage is 70 V or more.
8 Yes (70 V or more)
Are symptoms improved by replacing a power board with finished products?
8 Yes: Abnormality is found in the pull-up voltage on a QBC board.
Replace the QBC board. (Refer to Section 1-4-9.)
8 No: Abnormality is found in an AC detection circuit (AC OFF DET circuit).
Confirm the parts below using a test and replace them as required.
. D6002: Is D6002 not put into an open state or not short-circuited?
. Q6010: Is no problem found in the resistance value between terminals? (Is Q6010 not
short-circuited?)
8 No
The input voltage decreases.
Set the AC voltage to a normal level (77 V or more) and confirm it again.

3-4. System Does Not Start

The system does not start.
Are harnesses properly
connected?
Yes
Are symptoms improved by
connecting the finished products
of a G2 board?
Yes
Replace the OLED module
assembly.
(Refer to Section 1-4-9.)
3-8 (E)
No
Connect the harnesses properly.
No
Replace the G2 board.
(Refer to Section 1-4-3.)
PVM-A250