Troubleshooting Flowchart Step Descriptions - Sony KDS-50A2000 Training Manual

Troubleshooting Flowchart Step Descriptions

Reference Flowchart B, Figure 4-4 and Figures 4-5 & 4-6
When troubleshooting a "Unit will not turn ON" problem in previous
models the Red Power/Standby LED on the front panel, when illuminated,
would indicate that at least the Standby 5V power was functioning.
Unfortunately, there is no red standby LED on the 2006 SXRD models
(KDS-50A2000, KDS-55A2000, and KDS-R60XBR1). Therefore, the
only way to visually check if the Standby 5V circuit is functioning is to
press the ON/OFF power button and watching for the Green Power LED
on the front panel to begin flashing.
Does GREEN
The first decision diamond in Flowchart B asks the question – Does the
Green Power LED begin flashing? If the answer is yes then you know
that the Standby 5V and the TV Microprocessor are functioning (the TV
Microprocessor controls the Green LED).
The next step is to check the status of the Power LED. Does it Glow
Steady Green, Flash Excessively, or Flash Red.
If the Green Power LED glows steady then the Power-On sequence was
successfully completed, and the power supply system and microprocessor
communications are working fine. If there is still no video displayed or
audio heard then your troubleshooting efforts should be turned to solving
a video, audio, or lamp section defect.
TVP-23
Yes
LED Begin
Flashing?
What is the
State of the
Green LED ?
If the Green Power LED flashes excessively then there is a
communications problem between the microprocessors. In most cases,
it will be a communications problem between the TV microprocessor on
the A1-Board and the ATI microprocessor in the QM-Board. Confirm
that all cables and connectors between the A1-Board and the QM-Board
are securely seated and undamaged. If all connections are good then
the most likely defect suspect is the QM-Board. The fact that the unit
successfully completes the power-on sequence indicates that the TV
microprocessor is functioning properly.
If the Red Power LED begins flashing then the DE or TV microprocessor
have detected a system failure and has placed the unit in protection
mode. The Red Power LED flash sequence (number of flashes between
pauses) should be noted an proceed the indicated Protection Mode
troubleshooting flowchart(s).
Let us go back one-step in the flowchart and follow the path for the
situation when the Green Power LED does not begin flashing after the
unit receives an ON command.
The first step in troubleshooting a no Green Power LED symptom is to
confirm that the TV is securely plugged into a active AC outlet.
4. Power Supply System
Does GREEN
LED Begin
Flashing?
No
Is AC 110 V
No
Present
at CN 6014 ?
36