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Succesful repair: BenqQ FP91GX 19'' lcd screen

Blog entry posted in 'Repairs', Mar 27, 2014.

5.00/5, 1 vote
Got recently this lcd display, normal vga/dvi input computer monitor. I got it free, and i can't say no for free stuff (disease of some sort, i dunno :D...)
And free stuff is good in educational matter too. If it happens to blow up, not that big deal.
But, when i got home, i started looking for service manual, if i happen to find one. Well luck was in short supply seemed, and next step was to test it.
Seems it had strart-up problems. I was almost certain now that problems are caps, but how can it be certain without opening case up?.
This was easy enought to open, plenty of screws, only couple plastic clips. According some burglar marks, someone has attempted, or even succeeded opening this. Perhaps it's been faulty before?.

When i saw main board, i saw that PSU board was exactly same with one lcd screen i wasn't able to repair. like destiny/karma was playing with me.
Seems caps fault was indeed at least part of guess, bulky caps was seen pretty easily. only of HV cap i wasn't so concerned about.
Unfortunately, i didn't have correct low-esr caps on self, so had to order them. Luckily local service is fast enought, took couple days. This time i decided to order some extra, tired of ordering just that needed amount.

After i changed caps, next step was obviously putting case on, and testing time.

Testing came with interesting thing which i haven't encountered in lcd's before. 60w current limiter was enought that screen couldn't turn on. I didnt acknowledge this at first, but when limiter was bypassed, voila, works like charm (not my charm that is, that would need some refurbishing, i think)

Anyhow, towards next repair/teardown, or who knows?

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Gerry S., tvtech and ElectroMaster like this.
  1. ElectroMaster
    Great outcome Fezder :)
    ElectroMaster, Mar 30, 2014
  2. fezder
    Thanks, i have possible other lcd repair coming up, depeding how cheaply i can buy it, it's sorta auction. :)
    fezder, Mar 31, 2014