Wednesday, November 25, 2015

SONY KDL-26S2000 - KDL-32S2000 - KDL-40S2000 - KDL-46S2000 LED BLINKING CODE DESCRIPTION AND PROTECTION CIRCUIT

SONY KDL-26S2000 - KDL-32S2000 - KDL-40S2000 - KDL-46S2000 

LED BLINKING DESCRIPTION CODE AND PROTECTION CIRCUIT  

Protection System
Overall System Description
The failure protection system (aka. self-diagnostics routines) for the WAX2 chassis monitors the following circuits for abnormal conditions. If the TV microprocessor detects a failure it will activate the front panel StandbyLED, which will flash a unique RED pattern depending on the failure that occurred. The bullet list below lists all the monitored circuits and their unique flash pattern.
# 10.5V & Panel 5V Low-Voltage Protection (DCALERT3)
1X Red Power-LED Flash Pattern
# D5V Low-Voltage Protection (DC ALERT 2)
2X Red Power-LED Flash Pattern
# 3.3V & 1.8V Low-Voltage Protection (DC ALERT 1)
3X Red Power-LED Flash Pattern
# Backlight Protection
4X Red Power-LED Flash Pattern
# Overall Power Supply Protection
5X Red Power-LED Flash Pattern
# Audio Output Protection
6X Red Power-LED Flash Pattern
3 Internal Temperature Protection
7X Red Power-LED Flash Pattern
# TRIDENT (Scan Converter) Protection
8X Red Power-LED Flash Pattern
Protection Circuits Functional Description
NOTE: Make all voltage and signal measurements prior to the TV shuts down, and goes into the Protection Mode. There is approximiately a 20-second window before shut down. 
10.5V Low-Voltage & Panel 5V Low-Voltage Protection (1X Flash Pattern)
The service manual labels this protection mode as DC_ALERT 3. The 10.5V and Panel 5V supplies are monitored for a low-voltage condition. The 10.5V is monitored by the 4.7V zener diode D7500 and transistors Q7500 and Q7502 on the BU-Board. In normal operation D7500 is in the breakdown mode (ON) as long as the 10.5V supply stays above 4.7V. The zener has a voltage drop of 4.7V leaving 5.8V, which is applied to the base of Q7500 turning Q7500 ON and Q7502 OFF. With Q7502 OFF 3.1V is developed at IC1001/pin 154 (Main Microprocessor) through the voltage divider circuit of R7517 and R7518 using the Panel 5V supply voltage from switching regulator IC7000. If the 10.5V supply drops below 4.7V D7500 will turn OFF, Q7500 will turn OFF and Q7502 will turn ON, and a ground is applied to IC1001/pin 154 pulling the pin low. Consequently, the Main Microprocessor detects a 10.5V failure and the Red Standby-LED flashes a 1X pattern and the TV shuts down.
The Panel 5V is also monitor. The Panel 5V is the supply voltage to the voltage divder R7517 & R7518. The voltage divder circuit at its mid-point develops the 3.1V, which is applied to the Main Microprocessor. If the Panel 5V is missing at the top of the diuvider circuit the 3.1V will go low and the 1X protection mode is triggered.
D5V Low-Voltage Protection (2X Flash Pattern)
The service manual labels this protection mode as DC_ALERT 2. The D5V supply is monitored indirectly through the voltage divider consisting of R7515 and R7516 on the BU-Board. IC7005 regulates the 10.5V (from the switching regulator IC7000) down to 5V. The 5V (or D5V) is then applied to the Main Microprocessor IC1001/pin 153. If the D5V drops so will the 3.1V at the mid-point of the voltage divider. Consequently, the Main Microprocessor detects a D5V failure and the RED Standby-LED flashes a 2X pattern and the TV shuts down.
3.3V, 2.4V, & 1.8V LVP-Voltage Protection (3X Flash Pattern)The service manual labels this protection mode as DC_ALERT 1. This protection mode is activated if any one of the following regulators failures.
# IC7001 3.3V Regulator
# IC7002 1.8V Regulator
# IC7004 2.4V Regulator

Each regulator output is monitored by a transistor and a diode. IC7001 is monitored by Q7504 and D7508; IC7002 is monitored by Q7506 and D7510; IC7004 is monitored by Q7505 and D7509. The transistors are ON in normal operation, turned ON by the voltage output of each regulator. With the transistors ON a ground is applied to the anode of each diode, therefore, each diode is OFF (or reverse biased). All three diode outputs go to the base of a single transistor Q7503. The collector of Q7503 is connected directly to the Main Microprocessor IC1010/pin 163. In normal operation the voltage level at IC1001/pin 163 is 3.1V. If any of the three regulators failure the corresponding transistor (Q7504, Q7505, or Q7506) will turn OFF, and the ground is removed from the anode of the corresponding diode (D7508, D7509, or D7510). With the ground removed a high will be applied to the anode of the diode through the associated pull-up resistor (R7542, R7543, R7544), and the diode will forward bias, applying a high to the base of Q7503. The transistor turns ON applying a ground to IC1001/pin 163 pulling the pin low. Consequently, the Main Microprocessor detects a regulator failure and the RED Standby-LED flashes a 3X pattern and the TV shuts down.
Backlight Protection (4X Flash Pattern)
This protection mode monitors the operation of the Backlight Inverter Board and the Lamps. The Inverter Board is the Lamp power supply, which produces the high alternating voltage necessary to drive the ColdCathode Fluorescent Lamps (CCFL) used for the LCD panel backlighting. There are three main causes for the activation of this protection mode.
# Loss of 18.5V supply to the Inverter Board (at CN6202 on the
G2-Board)
# Loss of 3.2V Backlight ON signal
# Defective Inverter Board Circuits
# Defective Lamp(s)

The following paragraphs are brief descriptions of each failure listed
 Loss of 18.5V supply to the Inverter Board (at CN6202 on the G2- Board)
The 18.5V is the power supply for the Backlight Inverter board. However, the 18.5V also drives two voltage regulators on the BU-Board .Therefore, if the 18.5V is lost due to a Main Power Supply failure a 5X flash pattern is generated. The Main Microprocessor generates a 4X flash pattern only if there is a loss of 18.5V at CN6203. In other words, the Main Power Supply is functioning OK (producing 18.5V), however, the 18.5V is not making it to CN6203. There is a poor connection or open circuit in the physical connection between the G1/G2-Board and the Inverter Board. Consequently, the Backlight Inverter fails to start, the Panel Detect line goes low (CN7009/pin 3), and the microprocessor detects a failure.
Loss of 3.2V Backlight ON signal Confirm 3.2V at CN7009/pin 1 on the BU-Board. The Main Microprocessor on the BU-Board turns on the Backlight Inverter using the 3.2V Backlight-ON signal. You can measure this voltage at CN7009/pin 1 on the BU-Board. If the Main Microprocessor fails to send this signal (rare occurrence) or if there is an open path (confirm secure & undamaged connectors between the BU-Board and the Inverter Board) to the Backlight Inverter board then the Panel Detect line goes low (CN8603/pin 4) and the microprocessor generates a 4X flash pattern. Defective Inverter Board Circuits or Lamp Failure Confirm 18.5V (Power Supply) and 3.2V (Backlight-ON). In the case of an actual Backlight Inverter board circuit or Lamp failure, the 18.5V and the 3.2V voltages should be OK. Therefore, prior to shutdown you can measure these voltages to confirm that power supply and control signal are present. If these two voltages check OK, but the Backlight does not light and the Panel Detect line goes low (CN8603/pin 4) then the defect exists on the Backlight Inverter board or a Lamp(s) (Panel Assembly) has failed. Use the following procedure to determine whether the Backlight Inverter or the Panel Assembly is the defective component.
Caution: Do not attempt to directly measure the Backlight Inverter Board output directly. 1000V or greater is present at the outout on initail power ON.
The best way to check the Inverter Board output is to place your VOM probe on top of the individual plastic lamp connectors .Set the VOM to AC volts, place the probe on top of the connector directly above one of the two wires (each connector feeds two lamps). Place the VOM probe over each wire for proper measurements. A good output will measure approximately 3VAC.
A bad output will measure aproxiamatey 1VAC or less. If any single output is bad replace the Backlight Inverter Board. If all Inverter Board outputs are bad, check the 18V supply voltage from the Main Power supply before replacing the Backlight Inverter Board. If the 18V is missing check for loose or damaged connections between the G1/G2-Board and the Backlight Inverter Board. If the 18V is present at the Inverter Board, however, all output are bad then replace the Backlight Inverter Board.
Overall Power Supply Protection (5X Flash Pattern)
The purpose of this protection mode is to monitor and indicate a failure of the Main Power Supply (IC6100) on the G1/G2-Board. The primary voltage monitor is the 18V. If the Main Power Supply does start or remain running the 18V will not be developed and the Main Microprocessor will detect an overall power supply failure. The 18V is applied to the voltage divider consisting of R1031, R1034, and R1037. The voltage across R1037 (3.1V), which is stabilized and delayed by C1007 is applied to the Main Microprocessor IC1001/pin82. The presence of the 3.1V indicates a properly functioning Main Power Supply. If the 18V is not developed for any reason, then the 3.1V is not developed and the Main Microprocessor detects a power supply failure (5X).
 There is a multitude of failures that can cause the Main Power Supply shutdown. The following list identifies the possible failures.
# Failure of the Main Converter IC6100
# Loss of 3.3V Power-ON signal from Main Microprocessor
IC1001/pin 32
# Excessive 19V Supply to the PFC Circuit
# Failure of InRush Relay
# 18.5V Over-Voltage Condition

Main Power Supply Converter IC6100
Confirm that both the 3.3V Power-ON signal and the 18.5V increase, and stabilize to their respective levels before protection-mode shutdown. The presence of the 3.3V indicates that the converter IC6100 is most likely getting the necessary VCC input, and the presence of the 18.5V indicates that the converter IC6100 is starting and developing the secondary voltages, therefore, some other fault is shutting the TV down. It is rare that IC6100 will fail. This IC (MCZ3000D) integrated circuit has been very reliable in many previous chassis’s.
Loss of 3.3V Power-ON signal from Main Microprocessor
The Power-ON (or Power 1) signal is generate by the Main Microprocessor IC1001/pin32 on the BU-Board. The tricky part about troubleshooting this failure is determining if the Main Microprocessor is failing to generate the Power-On signal or if one of the two latch circuits (Q6202/Q6204 & Q6105/ Q6107) on the G1/G2-Board is pulling the Power-ON signal low. Notice that there are two latch circuits located on the G1/G2-Board. These latch circuits connect directly to the Power-ON signal line. If the Power-ON signal shows no signs of increasing towards 3.3V then the most likely failure is the Main Microprocessor IC1001. Before replacing the BU-Board check all connections between the BU-Board and G1/G2- Board.
If the Power-ON signal increases to 3.3V and then goes to 0V, then one of the latch circuits are being activated.
NOTE: The Power-ON signal can also be check unloaded. Disconnect CN6202/CN6203 from the G1/G2-Board and check if the 3.3V is present. If the 3.3V is present, then this indicates that the Latch circuits are activating due to a failure on the G1/G2-Board and pulling the Power-ON line low. One or more of the following events can trigger the latch circuits.
# Excessive 19V Supply to the PFC Circuit
# Failure of InRush Relay
# 18.5V Over-Voltage Condition
Loss of 18.5V (at CN7009 to the BU-board)

Confirm connections between G1/G2-Board and the BU-Board for the 18.5V path
Audio Output Protection (6X Flash Pattern)
The protection circuit (Q7014, Q7015, Q7016, Q7017, Q7018, and Q7021) mounted on the AU-Board monitors the audio amplifier outputs (speaker lines) for a shorted condition or for the presence of any DC voltage level (positive or negative). If either of these conditions is detected the protection circuit alerts the Main Microprocessor of the failure and the Standby-LED Flashes a 6X flash pattern.
Internal Temperature Protection (7X Flash Pattern)
The temperature sensor (IC1007) is mounted on the component side of the BU-Board next to CN1700. IC1007 monitors the internal temperature of the TV set, and communicates any temperature abnormality to the Main Microprocessor over the I2C bus. The following parameters affect internal temperature.
# TV Ventilation,
# Local External Temperature (Room Temperature)
# Internal Component Operating Temperatures

In most cases, one of the following actions will solve a temperature failure.
# Clear the TV areas of ventilation
# Relocate the TV set away from any area heating elements
# Provide adequate space between TV cabinet and walls (at least 4”)
# Replace Temperature Sensor IC1007
If the TV set shuts down immediately after turn-on and the Red StandbyLED indicates a temperature problem (7X flash pattern), then the most likely failure is the temperature sensor IC1007. The reason for this deduction is that a actual excessive temperature situation will take time to occur. The internal TV temperature must increase and IC1007 must detect the excessive temperature, and then communicate this information. to the main Microprocessor. This whole process takes time. However, if the temperature sensor (IC1007) itself has failed, the Main Microprocessor will not be able to communicate with IC1007 when the TV is first turned ON and the TV will, in comparison, immediately shut OFF.
TRIDENT Protection (8X Flash Pattern)
TRIDENT is the name for the integrated circuit (IC5000) that includes all the video processing circuitry, including the Scan Converter circuit. This protection mode monitors the operation of the internal Scan Converter. A failure of the Scan Converter is communicated over the I2C bus between the TRIDENT and Main Microprocessor, and a 8X flash pettern will occur.