This TV has a BN44-00214A power supply used in several models and there are lots of posts on it. Will start a new one here. Thought it was going to be an easy cap replacement.
TV had no standby power and a bulged CM858 680uF/25. After replacing the cap, there was still no power and I noticed the main 6.2A fuse was blown. I replaced it with a 8A, plugged it in and sparks flew.
The blue ceramic cap by the big filter cap had one leg blown out as well as a jumper beside it. The big Samwa filter cap was also bulged (not sure if it was bulged before). A little research indicated the dried out, brownish glue had become conductive causing more shorts. I replaced the big cap with a used one from another board, replaced the jumper and resoldered the ceramic cap (tester said it was still ok). I scraped off all the glue the best I could. Salvaged another 6.2A ceramic fuse and tried a second time. No sparks but still no power and it appeared the fuse blew a second time.
Did a bit of more investigating using clues from other posts and repair kits. Checking the bridge rectifier, there was a dead short between the + and - output pins which was traced back to a shorted QP801S (FCPF11N60 600V/10A). ICB801S (STR-A6159) could have been potentially damaged from the short but the fuse blowing could have protected it.
I replaced QP801S temporarily with a 2SK3326 (500V 10A) from another board and the TV finally powered up.
The ICL resistor is cracked (DSC_5D15) but measures 15 ohms instead of expected 5 ohm so I will need to replace this. Will order the correct FET but doesn't seem that 600V is necessary for the PFC since 400V is expected and 500V should provide enough headroom. I also forgot to install the old ferrite bead that was on the drain pin.
TV had no standby power and a bulged CM858 680uF/25. After replacing the cap, there was still no power and I noticed the main 6.2A fuse was blown. I replaced it with a 8A, plugged it in and sparks flew.
The blue ceramic cap by the big filter cap had one leg blown out as well as a jumper beside it. The big Samwa filter cap was also bulged (not sure if it was bulged before). A little research indicated the dried out, brownish glue had become conductive causing more shorts. I replaced the big cap with a used one from another board, replaced the jumper and resoldered the ceramic cap (tester said it was still ok). I scraped off all the glue the best I could. Salvaged another 6.2A ceramic fuse and tried a second time. No sparks but still no power and it appeared the fuse blew a second time.
Did a bit of more investigating using clues from other posts and repair kits. Checking the bridge rectifier, there was a dead short between the + and - output pins which was traced back to a shorted QP801S (FCPF11N60 600V/10A). ICB801S (STR-A6159) could have been potentially damaged from the short but the fuse blowing could have protected it.
I replaced QP801S temporarily with a 2SK3326 (500V 10A) from another board and the TV finally powered up.
The ICL resistor is cracked (DSC_5D15) but measures 15 ohms instead of expected 5 ohm so I will need to replace this. Will order the correct FET but doesn't seem that 600V is necessary for the PFC since 400V is expected and 500V should provide enough headroom. I also forgot to install the old ferrite bead that was on the drain pin.
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