Fix for Benq FP737s 17" (Q7T3)

[oddbodd]

Re: Fix for Benq FP737s 17" (Q7T3)

I'm in the middle of resoldering, and have just come across an unsoldered pin on T601. Is that right?

Edit: Answering my own question, I've see on post #244 there's a picture of the same board, with the same pin unsoldered.

[oddbodd]

Re: Fix for Benq FP737s 17" (Q7T3)

Good news. I now have a working monitor again!

I was almost ready to call it a day. After desoldering/resoldering everything suggested in the earlier post... it still didn't work.

So I retested the new C5707s and found that one pair had gone bad. So I removed them and reinstalled 2 of the original 4, all of which had tested OK after they were removed.

So I got there in the end, even if I did get a bit of a headache using a magnifying glass for so long!

I just hope it keeps working...

Thanks to all who helped.

[selldoor]

Re: Fix for Benq FP737s 17" (Q7T3)

Hi -Well done! This often happens unfortunately. The 5707s are shot and are replaced but if the soldering is not redone then they go again as it is the main reason they went bad in the first place.

To increase its life expectancy you could also replace the middle size caps
if not all except the BIG one.

[oddbodd]

Re: Fix for Benq FP737s 17" (Q7T3)

Yes, I think that should have resoldered first and then replaced later. Lesson learnt.

I'll bear that in mind, about the caps, too. Thanks

[Behemot]

Re: Fix for Benq FP737s 17" (Q7T3)

I am just curious, did somebody found the final solution? From what I remember when I've read this through half a year ago, I remember davmax found there are some spikes when the display goes off and back on right again while restarting system (pre-POST). I also think I remember he thought he found the solution but than the 2SC5707 just blew again…

[R_J]

Re: Fix for Benq FP737s 17" (Q7T3)

I just repaired a Dell E173FPb (Benq board) that had one shorted 2sc5707, and the cause was poor solder connections on components in the inverter, (transformer and cap. c735) plus other misc. poor connections.