Mag LT916s Model 900p 19" LCD dropping like flies

[Hedgehog52]

Re: Mag LT916s Model 900p 19" LCD dropping like flies

MAG 900P

i also have the same problem 2 secs. shutdown... by replacing the 2 caps rated 100uf 25v (c10) and (c11), the problem solved....

Thanks for this post! My PL916S failed several years ago and, after changing the larger caps to no avail, I set it aside. Today, I got in a good "pull" from shopjimmy.com and so my monitor is now working, but I thought I'd revisit badcaps.net. I can't say why I didn't try changing C10 and C11 back when, but I didn't, and looking at the board they seem the obvious next step. I think I'll go ahead and change them on my old board and put it on the shelf for the next time.

Thanks again!

[littlejoenc]

Re: Mag LT916s Model 900p 19" LCD dropping like flies

Hi guys new here and I'm kinda reviving this old thread...
I just ordered a new board from shopjimmy for a LT982s and was wanting know if I should go ahead and replace the caps on the board brfore I install it..


Thanks Kenneth

[PlainBill]

Re: Mag LT916s Model 900p 19" LCD dropping like flies

Hi guys new here and I'm kinda reviving this old thread...
I just ordered a new board from shopjimmy for a LT982s and was wanting know if I should go ahead and replace the caps on the board brfore I install it..


Thanks Kenneth

Well, it's a little late. You should have replaced all the caps (except possibly the 100uF, 450 volt one) before you ordered the replacement board.

Since you have already ordered it, order the caps, test the new board, then recap it ESPECIALLY C10 and C11.

PlainBill

[littlejoenc]

Re: Mag LT916s Model 900p 19" LCD dropping like flies

This is why I ordered a new board..
A lot of heat and the burnt chip...
What isthe chip that is brunt?
The # on the chip is 4606 and BD4332

[PlainBill]

Re: Mag LT916s Model 900p 19" LCD dropping like flies

This is why I ordered a new board..
A lot of heat and the burnt chip...
What isthe chip that is brunt?
The # on the chip is 4606 and BD4332

That board has been overheated; I've seen worse. Considering the value of a 19" LCD monitor I'm not sure if it is worth repairing (other than as a matter of pride). (I just replaced a bad CCFL in a 19" Dell monitor. By the time it is sold I will have worked for about $5.00 an hour. Not a good use of my time.)

I'm sure the IC that has shorted is listed somewhere else in the thread. It is either a dual complementary mosfet (identical to the one near it), or a dual n-channel or p-channel mosfet - the complement of the one above it.

PlainBill

[littlejoenc]

Re: Mag LT916s Model 900p 19" LCD dropping like flies

(I just replaced a bad CCFL in a 19" Dell monitor. By the time it is sold I will have worked for about $5.00 an hour. Not a good use of my time.)

PlainBill

I understand that...
For $35.00 Including shipping, I fixed it cheaper than I could buy a used one around here, Plus learned a few things...Always good to learn....

Thanks

[jetadm123]

Re: Mag LT916s Model 900p 19" LCD dropping like flies

That board has been overheated; I've seen worse. Considering the value of a 19" LCD monitor I'm not sure if it is worth repairing (other than as a matter of pride). (I just replaced a bad CCFL in a 19" Dell monitor. By the time it is sold I will have worked for about $5.00 an hour. Not a good use of my time.)


PlainBill

If you include your time helping others on this forum, then it brings you down to about 99 cents/hr.

[PlainBill]

Re: Mag LT916s Model 900p 19" LCD dropping like flies

If you include your time helping others on this forum, then it brings you down to about 99 cents/hr.

That's the good news. My life has made a U-turn. 46 years ago I worked on a 'truck' (produce) farm for $1.00 per hour. That was a step up. The previous job was working on a dairy farm shoveling manure for $2.00 per day (starting wage was $1.00 per day). The good news was I got to drive the tractor pulling the manure spreader!! (You really don't want to know).

PlainBill

[thingonaspring]

Re: Mag LT916s Model 900p 19" LCD dropping like flies

Hi guys,

I was given a scenicview E19-1, Model N900p which had would run OK for 5 mins, then switch off. Pressing power or changing screen res would cause the screen to come back for 2 seconds, then off again.

I've replaced caps C10 and C11 and all is working well now. I know the rest of the caps are probably dodgy, but I'll fix those as and when they fail.

The result is - I got a nice working monitor for a total cost of 50 pence, very cool.

[pavedom]

Re: Mag LT916s Model 900p 19" LCD dropping like flies

Hi, i have this inverter on Scaleoview C19-6.
All capacitors are defect, i changet this with Rubicon.
But is defect one SMD Transistor U2 - D444 on
https://www.badcaps.net/forum/attach...8&d=1272830116

Cann you help me identifi this Trnasistor?

[PlainBill]

Re: Mag LT916s Model 900p 19" LCD dropping like flies

Hi, i have this inverter on Scaleoview C19-6.
All capacitors are defect, i changet this with Rubicon.
But is defect one SMD Transistor U2 - D444 on
https://www.badcaps.net/forum/attach...8&d=1272830116

Cann you help me identifi this Trnasistor?

They are Alpha & Omega AOD444 transistors. They are available on eBay.

PlainBill

[ciederanbadcaps]

Re: Mag LT916s Model 900p 19" LCD dropping like flies

To "PlainBill"
Hello
Excuse my english first of all. I've seen your posts on badcaps and all of them were very accurte, so I guess you might help me with next problem: 'two seconds to black' problem in a Fujitsu-Siemens 19"LCD Monitor wich acttualy is Proview Scaleoview C19-3 Model 900P with power-source/inverter board MIRAGE ELECTRONICS CO., LTD. / AD-1700 REV:F 200-000-170DTL1 VERSION:A. I found many of your explications on thread "Mag LT916s Model 900p 19" LCD dropping like flies". I will replace all ElCaps with new ones and LowESR, but I measured 352Ohms and 347Ohms as you asked someone to measure in post nr. 126 "https://www.badcaps.net/forum/showpost.php?p=103941&postcount=126" (I have the exactly same board), that guy measured 366Ohms I presume on both measuring points (blue and yellow). My question is if and how this difference can affect the board's functionality. Many thanks.
best regards
Cosmin

[selldoor]

Re: Mag LT916s Model 900p 19" LCD dropping like flies

Hi welcome to the forum
Plainbill seems to be taking a break at the moment - we are missing him.
I dont know if the difference will affect the board's functionality - at a guess it could make the backlight ccfls slightly brighter or dimmer. Perhaps someone else will respond with a better informed reply.
I believe the actual measurement is not too critical, the important thing is that two inverter transformers are matched and the resistances are within 3% of each other , and of course it is to check that they are not open or shorted.

[ZLemur]

Re: Mag LT916s Model 900p 19" LCD dropping like flies

I somehow (don't ask) managed to destroy zener diode z202 on this board... Does anyone have the foggiest what the numbers associated with that are? It's broken enough to not be able to read any of the print on it. I'd really really appreciate it! Thanks in advance!

Also, this thread is likely going to net me a 19" monitor that's been sitting in my closet for years! (I have no idea how I managed to let it survive 3 moves without tossing the the thing since it stopped working!) Thanks so much for the info so far!

[tom66]

Re: Mag LT916s Model 900p 19" LCD dropping like flies

Z202 is an overvoltage protection device - monitor will work without it, and it will not really protect anything. The idea is that the zener will conduct and blow the fuse if there is an overvoltage on the PSU, but in reality it will just melt. If you want, you can replace it with a 6.2V 1W DO-41 zener if it's on the 5V rail, or a 15V 1W DO-41 zener if it's on the 12/13V rail. Leave about 1V margin.

I had a Xerox 19" with the same symptoms - I just replaced all the caps (Xunda) with Chemicon KY and Panasonic FM - still going strong about 18 months later.

[ZLemur]

Re: Mag LT916s Model 900p 19" LCD dropping like flies

Thanks Tom - that's exactly what I needed to know!

Also, is it just me, or is that kind of a peculiar use for a zener diode in this case?