Benq FP931 Q9T3 bulged Elite Caps

[vince88]

Just got a non-working Benq FP931 Model Q9T3 manufactured July 2004. On power ON, the screen will light up with moving green light pattern, then fully white, then dark. No picture, but the LCD would respond to input, turning itself ON when connected to a VGA source, the OFF after 5 secs.
When Opening the LCD, I found three boards [1] a small control board with the buttons, linked to connector J3 of #2 board [2] a graphic processor and LCD driver board 48.L0G01.A00 [see pic GPboard] connected to the LCD panel and to the #3 board [3] a power and backlight board 48.L0G02.A00 [see pic PwrBlight] connected to 120-240VAC and to 4 backlight lamps. On the power board, 4 caps were bulging, see pic Caps. These are all Elite 105 degC [a] C818 470micF 25V [b] C703 1000micF 25V -adjacent C704 is OK- [c] C707 and C708 both 1000micF 16V. Waiting to get 1000micF, I replaced all 'bulgers' by 470micF 25V 105degC from my component box: the LCD is now working fine.

[retiredcaps]

Re: Benq FP931 Q9T3 bulged Elite Caps

Benq boards have problems with their poor solder joints on the following:

1) inverter transformer pins (T801, T802)
2) c5707/fu9024 transistors (looks like QQ812, Q815, Q816, Q809, Q806, Q808?)

Reflow/resolder to prevent possible future short of the transistors.