Audio Output Error (7X); Panel Error (9X) - Sony KDS-R50XBR1 Training Manual

Audio Output Error (7X)

This error is relatively straightforward. The error occurs when one of the
audio outputs is shorted or if a DC voltage level is present. In either case
the problem exists on the audio board (K-Board).
Remove the K-Board to verify that the K-Board is causing the TV to
shutdown (7X).
If the K-Board is defective, the TV will turn on with video and no audio.
If the TV still shuts down (7X), then the problem is with the DE
microprocessor, and consequently, the ASU/DSU assembly must be
replaced.

Panel Error (9X)

Microprocessor I 2C
Communications error
This error is somewhat deceiving because of the name Panel Error. An
actual defect LCD display will not cause this error or any error for that
matter. The likely reason for the name Panel Error is that a defective C-
Board, which is the LCD display driver can cause a (9X) error. The S1-
Board and the S2-Board can also cause a (9X) error.
The fundamental defect that causes this error is a loss of I2C
communications (or Inter-IC Acknowledgement) between the C-Board,
S1-Board, or S2-Board and the DE microprocessor. One or more of
TVP-21
7X Flash
Pattern
(Audio Output )
Remove
K-Board
9X Flash Pattern
these three boards have failure to communicate (or acknowledge) the
De microprocessor. Therefore, the fist step in solving the problem is to
check for loose or damaged connections between all three boards and
the ASU-Board or the DSU-Board (Reference Figure 4-8). Secure and/
or repair connections where needed.
DSU-Board
CN7956
I2C
WE
IFP
Micro
TV
Micro
Inter-Board Connections
Microprocessor Power Supplies & I2C
Communications Diagram
If all the inter-board connections are OK, then the next step is to determine
which board has failure and is not communicating over the I2C bus. At
this point you could just begin substituting known good boards to find the
faulty board. However, to be more effective and efficient you should first
confirm that each board is receiving the proper supply voltages. This
step will quickly eliminate or detect a power supply failure, in which case,
you need to go to the Power Supply Flowchart (B) and troubleshoot a
power supply problem.
4. Protection Circuits
Check & Secure the
following Inter-board
connections
S1 to ASU
S2 to ASU
C to DSU
C-Board
CN6901 CN6900
4
/
ROOK 6.5V
6
ASU-Board
CN2303
CN7120
7
5V &
11
I2C
DE
CN7100
Micro CN2303
Ambient Thermal
Figure 4-8
S2-Board
5V
Lamp Thermal
Sensor
S1-Board
5V
Sensor
78