Hello all.
The last months I've repaired many Samsung LCD's in the models LE40R86, 87, 88. They all had the well known secondary cap failure. BUT, I would say 75% of the sets doesn't come on properly after cap replacement. Then, all is needed is to change IC1803 (ATMEL 24C256), one of the mainboard EEPROM's. My theory is that when the mainboard starts up and detect the eeprom is empty, it will dump over the correct data stored somewhere else, probably in the flash. This has cured EVERY tv set without problems until today.
You may wonder why the eeprom gets corrupt in the first place, but my theory is that the bad caps filter the supply lines so badly, there will be excessive noise and spikes on supply lines. This will result in corrupt data in the eeprom.
The model is the LE40R81, very very similair but another kind of mainboard. Though, the eeprom is still designated IC1803.
After cap AND eeprom replacement (it didn't work without changing the eeprom) the sets comes up, works perfectly, in 29 seconds. Then it shuts itself off and make a new start up, works in 29 seconds and continues to do like this over and over again. Since this is actually the first time I work on a LE40R81 (did only 86, 87 and 88's) may this board need other eeprom's replaced aswell?
The last months I've repaired many Samsung LCD's in the models LE40R86, 87, 88. They all had the well known secondary cap failure. BUT, I would say 75% of the sets doesn't come on properly after cap replacement. Then, all is needed is to change IC1803 (ATMEL 24C256), one of the mainboard EEPROM's. My theory is that when the mainboard starts up and detect the eeprom is empty, it will dump over the correct data stored somewhere else, probably in the flash. This has cured EVERY tv set without problems until today.
You may wonder why the eeprom gets corrupt in the first place, but my theory is that the bad caps filter the supply lines so badly, there will be excessive noise and spikes on supply lines. This will result in corrupt data in the eeprom.
The model is the LE40R81, very very similair but another kind of mainboard. Though, the eeprom is still designated IC1803.
After cap AND eeprom replacement (it didn't work without changing the eeprom) the sets comes up, works perfectly, in 29 seconds. Then it shuts itself off and make a new start up, works in 29 seconds and continues to do like this over and over again. Since this is actually the first time I work on a LE40R81 (did only 86, 87 and 88's) may this board need other eeprom's replaced aswell?
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