The LCD Panel Assembly includes the LCD Panel, TCON Board, and LED Back-light system.
The LCD Panel contains the actual liquid crystals, color filters, and polarizers. The liquid crystals are manipulated by the applied voltage to pass a specific amount of light - from the back-light - depending on the level of voltage applied.
The TCON performs all the control, timing, charge, and discharge functions driving the operation of the LCD Panel.
TCON Board (Internal - not available as a replacement part.)
The inverter receives the unregulated 24V from the Power Supply Board and generates the required high voltage AC to power the backlight lamps. A control line to turn on the inverter (backlights on) is used in conjunction with a dimmer control to vary the light level of the CCFL lamps.
SELF DIAGNOSIS FUNCTION
Critical voltages and circuit operations are monitored by the CPU on the Main Board. If an error is detected the Self Diagnosis function in the TV will force the TV to shut down by the CPU. The monitored circuit in which the fault occurred will automatically cause the CPU to blink the Standby LED in groups of repeating sequences. The number of times the Standby LED blinks indicates the possible cause of the problem.
Not all of the available protect codes are used in every model. For example, models that don’t have the local dimming feature do not use the 4X blink error as this circuit is found in models that are back-lit with fluorescent lamps. The information in this section provides guidance in locating the possible component causing the shutdown.
UPDATING THE SOFTWARE
The Self Diagnosis function is designed to provide information regarding the problem with the TV, however, there are several issues that may be resolved by updating the TV software to the latest version. Always check for any issues that are software related. Most symptoms that are correctable by software updates involve communications issues with other devices or minor glitches in the operation of a specific function. Below is a list of some of the symptoms that may be corrected with a software update:
Fluctuations in picture brightness
Intermittent picture freezing or noise
Problems with certain inputs (especially HDMI)
Intermittent or distorted audio
Erratic remote control operation
TV turns on and off by itself
Loss of color
Internet connectivity
Certain features not working correctly (photo or video file viewing)
VIEWING THE SELF CHECK DIAGNOSIS HISTORY
When an error is detected, the Self Check screen records the error that occurred. This is helpful in confirming past occurrences of an error, and for determining if an error is intermittent when the customer is not sure what is causing the television to shut down. If the screen displays a “0”, no error has occurred.
You must got into Service Mode to access the Self Check menu.
1. TV must be in Standby mode. (Power On).
2. Press the following buttons on the Remote Commander within a second of each other:
To access the Self diagnosis history page, press the DN button until Self diagnosis history is highlighted, and then press (+)
To exit the Self Check, press MENU
Review the information to determine the most likely source of the error.
Standby LED blinking codes details
2X Blink - Main Power Error
A loss of REG12V from the power supply triggers this protect event. The usual cause is a failure of the main switching supply. In some instances, excessive loading on the secondary supply lines can cause the switching regulator to stop, or fail again, if a replacement board is installed.
3X Blink- DC Regulator/Audio Error
The REG 5V and D3.3V source originating on the Main Board is monitored for low-voltage conditions by the CPU. A failure causing a 3X shutdown requires replacing the Main Board.
4X Blink – Balancer Error NOT USED IN THIS MODEL SERIES
The 4X error code is only used on models incorporating local dimming LED backlighting. If a failure occurs on the LD board or one of the LED’s fails in the panel the TV will shut down and display this diagnostic code. Models using conventional non-local dimming LED backlighting do not utilize this error code.
5X Blink - TCON Error/Panel Error
The 5X blink protection mode indicates a communications error with the timing control circuits (TCON Board) has occurred. If the TCON Board is available for replacement, replace it, if not, replace the LCD Panel Assembly. In rare cases a loose or defective LVDS cable could also be the cause.
6X Blink - Backlight Converter System Failure
If the inverter circuits fails to generate high voltage or one or more of the backlight lamps fails to light, the television will shut down and display this diagnostics error. Observing for the presence of backlighting is crucial in determining which component is likely at fault.
If the backlights turn on before the 6X shutdown occurs, it is safe to assume that the inverter circuits are functioning and one of the lamps failed to ignite. Replacing the LCD Panel assembly is necessary. If the backlights never turn on before the 6X shutdown, the Inverter MT Board has failed. If this board is available for replacement, replace it, if not, replace the LCD Panel Assembly.
7X Blink - Temperature Failure
A digital thermometer IC located on the Main Board provides a temperature reading of the chassis and LCD panel. If the temperature exceeds a predetermined point the TV will shut down. If this problem occurs immediately at turn-on, the temperature sensing IC has failed and replacing the main board is required. If this occurs after the TV has been running for a while, check for ventilation issues that could cause the TV to run hotter than normal.
Disassembly
Gently place LCD TV face down onto a soft cloth and remove 3 screws from Table-Top Stand.
Remove screws from Rear Cover.
15 from KDL-32BX355 Only
17 from KDL-40BX455 Only
19 from KDL-46BX455 Only.
Do not damage the Power Board Connector and AC Power Cord when removing the Rear Cover.
Carefully lift Rear Cover from bottom side and push forward to release top hooks.
Hold Power Supply Cord while lifting up Rear Cover, then pass Power Supply Cord through Rear Cover opening.
Updates and adjustments
The models discussed here utilize a “generic” type of Main Board, therefore a software update must be performed and certain service adjustment settings must be changed or confirmed whenever the Main Board, LCD Panel, or TCON Board is replaced.
There are 2 reasons for updating the software on the TVs.
Software updates for customers
These updates are for enhancements or improvements that have been made to the software after the TV was released.
Software update for servicers
These updates are specifically for servicers to use during a service call.
The subject of software updates is very important. The televisions of today have advanced to the point where they are not simply a television anymore.
They are evolving into devices that are designed to integrate with numerous other devices found in the home. Some examples are: portable audio and video devices, still cameras, home computer networks and accessing the internet to name a few. Communications with these varying devices requires that the television be
compatible with varying communications protocols. Although standards are detailed for each of these protocols, the real world dictates that occasional errors may occur that could prevent devices from operating or communicating properly.
Keeping the software in the television up-to-date is a procedure that is normally handled by the owner of the television. Most customers who own computers and other digital devices are familiar with and are accustomed to updating the software in their products. If a customer contacts the Sony Customer Support Center and it is deemed to be correctable with a software update, the issue is handled at the customer level.
Software updates can be performed by:
Customer Manual Downloads: Software updates can be performed by the customer by placing it on a USB device to be loaded onto the TV. The instructions for downloading the software file vary from chassis to chassis and sometimes from model to model.
The customer is provided with the instructions to properly format the USB device, unzip the file, and the procedures for loading the software into the television.
Network Downloads: Internet software updates are becoming more prevalent as more and more models incorporate home network capabilities. This method is the most practical since the television will check for the latest version of software. The models with this type of chassis provide the customer with a choice of
turning the automatic software update feature on or off. If set to on, the television will lookup software information while the unit is in standby. If a newer version is available, it will be downloaded and installed without any input from the customer.
Built-in Tuner: OTA or cable sources having the proper station that is transmitting software update data packets. Although the ability to transmit software update is possible in this way, it is the least common and is reserved for particular situations where a critical update is “forced”, thereby updating the TV without any input from the customer.
SOFTWARE UPDATES FOR SERVICERS
Replacement Main Boards are now stocked with basic software. Once the replacement board is installed in the TV, the most current software needs to be installed using a USB device containing the necessary software.
This new method of supplying Main Boards significantly reduces the complexity of replacing the Main Boards. Information about the LCD panel is stored on the TCON circuits. This information is automatically loaded onto the Main Board when the TV is powered up. With the correct software version the Main Board and/or the TCON can be replaced more efficiently.
SOFTWARE UPDATE RESPONSIBILITY
Software updates are designed to be performed by the customer. Warranty repairs in which the issue can be resolved by a software update are not reimbursable. Most issues involving software updates are handled by the customer service center and should not be directed to an authorized service center. It is the responsibility of the servicer to prevent service calls for issues that involve software updates. Exceptions to this are certain cases whereby the customer is unable or unwilling to perform the task. In this situation, the servicer will be notified and receive the proper authorization for reimbursement.
It is the servicer’s responsibility, however, to make certain that any TV requiring a legitimate service is running the latest software version and to install it if necessary.
CHECKING THE SOFTWARE VERSION
The easiest way to check the version of software that is currently on the TV is to access the Contact Sony screen by using the customer menu.
EXAMPLES OF SOFTWARE CORRECTABLE SYMPTOMS
Always check for any known and/or listed issues that are software related. Most symptoms that are correctable by software updates involve communications issues with other devices or minor glitches in the operation of a specific function. Below is a list of some of the symptoms that may be corrected with a software update:
● Fluctuations in picture brightness
● Intermittent picture freezing or noise
● Problems with certain inputs (especially HDMI)
● Intermittent or distorted audio
● Erratic remote control operation
● Unit turns on and off by itself
● Loss of color
● Internet connectivity
● Certain features not working correctly (photo or video file viewing)
ACCESSING SERVICE ADJUSTMENT MODE
TV must be in Standby mode. (Power On).
Press the following buttons on the Remote Commander within a second of each other:
COMPLETING SERVICE REQUIREMENTS WHEN REPLACING THE MAIN BOARD
The following must be performed after replacing the Main Board to ensure that all of the features for the TV will be available.
Viewing the status information.
Adding the serial number.
Selecting the model name.
VIEWING THE STATUS INFORMATION
After replacing the Main Board, LCD Panel, or TCON Board, you MUST UPDATE the SOFTWARE to the latest version. Verify the latest software is installed before proceeding to the service adjustments.
Press the [DN] until Status Information is selected, then press [+]
Verify the latest software version is installed.
Do one of the following:
If the latest software is not installed, update the software and then proceed to Adding the Serial Number.
ADDING THE SERIAL NUMBER
Verify before proceeding to the next step:
Verified Status Information
TV must be in Standby mode. (Power On).
Press the following buttons on the Remote Commander within a second of each other:
Locate the serial number for the TV on the side of the Rear Cover of the TV
Using the Remote Commander, enter the correct serial number.
Proceed to selecting the model name.
SELECTING THE MODEL NAME
Verify before proceeding to the next step:
Verified Status Information
Added the Serial Number.
From the Service Mode menu, press [DN] until Model Name Edit is selected, and then press [+]
Using the Remote Commander, enter the correct Model Name.
To save the change, press [+]
To exit the Self Check, press MENU
COMPLETING SERVICE REQUIREMENTS WHEN REPLACING THE LCD PANEL
The following must be performed after replacing the LCD Panel.
NOTE: The TCON Board is internal and cannot be replaced.
Viewing the Status Information
Changing the LVDS Spectrum
Selecting the LCD Panel
1. TV must be in Standby mode. (Power On).
2. Press the following buttons on the Remote Commander within a second of each other.
VIEWING THE STATUS INFORMATION
After replacing the Main Board, LCD Panel, or TCON Board, you MUST UPDATE the SOFTWARE to the latest version. Verify the latest software is installed before proceeding to the service adjustments.
Press [DN] until Status Information is selected, then press [+]
Verify the latest software version is installed.
Do one of the following:
If the latest software is installed, proceed to Changing the LVDS Spectrum.
If the latest software is not installed, update the software and then proceed to changing LVDS spectrum.
CHANGING THE LVDS SPECTRUM
Verify before proceeding to the next step:
; Verified Status Information.
Press the [DN] until LVDS Spectrum (%) is selected.
Press [ç or è] to change the data value.
Proceed selecting the LCD panel.
SELECTING THE LCD PANEL
Verify before proceeding to the next step:
Verified Status Information
Changed the LVDS Spectrum
Press [DN] until Panel Selection is selected.
Press [ç or è] to select the correct panel for the model being repaired.
To save the changes, press [UP] until the Back is selected, then press [+]
Proceed to wide band tuning adjustments
TUNING ADJUSTMENTS
