I've got this unlucky board, a Vestel 17IPS20P (150313R3) that got a couples surgeries during its lifetime. The last time I fixed it there was a blown diode (D208), nothing extraordinary, happened already two years ago, changed it and everything was fine. Then after about a month I had the brilliant idea to add the unpopulated diodes D207 and D505 to harden this weak spot. During this operation I must have splattered some solder on the HV section cos after closing the lid and giving power a loud boom happened.
U202, S536, Q211, R230, R22, R242, D201, D208, D228, D522, D523 were destroyed.
Removed the extra diodes, replaced these parts and now the board is pulsating. It makes a clicking noise in the region of TR200. VCC_MAIN and VCC_M are trying to reach operational voltage during these pulses. From time to time if you let the board do this thing for a minute or two it may start and give around 10V on +12VCC and 20V on C217, the TV backlight turns on briefly as it should and the red standby led stays on (there is a buzzing noise, maybe caused by the undervoltage). Trying to use the remote to turn on the TV makes it cycle back to pulsating.
Not sure what to do now, the pulses and the damaged components on the FB_M line could mean a bad U200, but i tried with a 3171 (should be compatible) and nothing changed.
U202, S536, Q211, R230, R22, R242, D201, D208, D228, D522, D523 were destroyed.
Removed the extra diodes, replaced these parts and now the board is pulsating. It makes a clicking noise in the region of TR200. VCC_MAIN and VCC_M are trying to reach operational voltage during these pulses. From time to time if you let the board do this thing for a minute or two it may start and give around 10V on +12VCC and 20V on C217, the TV backlight turns on briefly as it should and the red standby led stays on (there is a buzzing noise, maybe caused by the undervoltage). Trying to use the remote to turn on the TV makes it cycle back to pulsating.
Not sure what to do now, the pulses and the damaged components on the FB_M line could mean a bad U200, but i tried with a 3171 (should be compatible) and nothing changed.
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