Why can be sharp protect on the sharp tv
Protect mode applied to almost all brands of television as a security system that prevents the damage from spreading to other components, and not burnt other components.
It would be okay to implement the system protect, we seldom see any component until charred, because when the system detects a fault current which should not be, then the system protection will soon be working.
But with the system protect on the modern televisions, it is sometimes ake little difficult to the technician to determine the actual damage. For that let us see good description of points that could lead to protect the sharp television.
1. IC memory or EPROM
Why eprom could lead to protect? for modern television, all systems of the circuit is determined by an IC memory, such as the width and height of the image, the bright and dark images, data storage broadcasts and others.
If the system memory is no longer able to work properly, there will be no synchronous working circuit, which would cause the program receives a signal that something wrong with ic memory, whatever the reason the system in a fixed program will draw the conclusion that there has been damage to one circuit, so the television will soon turn itself on protect mode.
How to overcome the damage IC memory or EPROM
Actually, there are two ways to improve memory ic are:
- Try to reset it, reset the data memory ic according to the type of television is concerned.
- Replace it with a new IC memory if the ic memory not able to save the data as usual.
How to reset IC memory on TV Sharp
some types of tv provide reset menu that can be accessed by pressing a combination of buttons on the casing tv. make sure you read the manual to find these features.
Other ways you can do with the hard way ie through the circuit board is in television.
For sharp tv in protect mode, to reset the memory that is by connecting a short wire located on the pcb holes with code pcb 122 and 124, then after appearing factory menu, please do a reset to enter the right data, how we know the data is correct, then we are obliged to note that all of the correct data on a television that is still in good condition.
Well if by doing a reset didn’t solve the problem, this meaning the ic memory should be replaced with a new one, but it must be remembered that ic memory sometimes is still empty, or there would not be the right data at all for the television.
Then how to replace the IC memory sharp tv
How to change the IC memory on sharp television without setting data reset.
Unplug the old ic memory, and replace the ic memory with the new one and completely empty from any data, it is time we do the trick, a direct dial jumper wire 122 and 124 are located on the pcb holes as that mentioned earlier, in order to there was no trouble, the jummper should be soldered well.
Now plug the AC cord to a power source, allow some time until the television is lit perfectly, after the television is lit perfectly, just off the solder jumper wire was in a state television was still on, complete do with carefully, and if the way this is done properly, then ic memory will be filled automatically without having to do manual settings.
2. Vertical Circuits IC
Why vertical circuit could cause sharp protect? If The series of vertical IC is working properly, it will generate a sine wave onwards will be accepted by ic program, well, if ic vertical not working properly, then the wave frequency that shall not be accepted by ic program, and with automatic ic program will do its job is to protect that damage does not spread to other components.
Components that are often damaged in a series of vertical
Here are some components that are often damaged in a vertical series of sharp tv:
- Elco 470 uf 63 volts which filters voltage 45 volt for vertical ic purposes, the damage usually is the dryness of the electrolyte in Elco.
- Elco 100 uf 63 volts as a second filter voltage 45 volt get dry
- Resistor 33 ohm 1 watt with code pcb R505 has broke
- small Diodes mounted underneath the pcb with code D814 and D815 has leak
- It could also which is the vertical ic TDA 8357 already damage.
3. The diodes on the input and the inverting input vertical
Damage to the diode may be the cause protect mode, often leaking or half short-circuit, so that the oscillator signal for inverting input and vertical input becomes impaired, and certainly will cause sharp tv be protected.
Damage to the diode is usually marked by darkness on screen tv with a small line appears on the screen and shortly thereafter tv go into protect mode, the solution to this kind of damage, simply remove the two diodes, the TV will turn on again without the need to replace the diodes with the new part.
4. The diode rectifier to voltage 45 volt and 12 volt half drop out
Often some voltage of 45 volt and 12 volt less than it should, after the checking is done carefully, evidently, is already in the short-circuit state, you can replace it with a diode IN 4007 or IN 4004.
5. Pin Protect from video amplifier voltage of 180 volts and afc
If you notice on the circuit board, you'll find two zener diodes premises code pcb D610 and 607, each of which the negative part is connected to a small transistor, hat tiny transistors collector is connected to the video output amplifier 180 volts, and the D607 is connected to a voltage FBT foot section of afc, if one of the components connected to the transistor is damage, it will cause sharp tv protect.
Please do measurements to all components which connected to the voltage of 180 volts and the voltage afc, such as resistors, Elco, diodes and others, will be found one of the components that change the value or dropped out altogether, most often damaged are usually resistor 56k , 22k, and 10k are changed values, had also discovered damage to the elco video amplifier 10 uf 250 volts is get dried.
6. Resistor ABL break up
Why break ABL resistor can cause sharp tv protect? abl resistor with size 39K works as a voltage abl divider forwarded to the IC oscillator, if the resistor is broken, then the voltage will be slightly enlarged, and automatically program the system will detect a malfunction, so the TV will automatically protect when the light is too bright.
That's 6 points cause sharp tv protect, in fact there are many more that could lead to sharp tv protected, such as damage Tunner, damage ic audio and others, because each set is equipped with sensors protect which will give the command protect the ic program if there is something wrong in the system.
It just for information purpose only, if you have no idea how to fix it please contact your technical support. at least, this way you know what roughly causing sharp tv get in to sharp protect mode and you know what your technical support will do with your television
May be useful.
