I'm helping a friend trying to repair their tv. It's a Philips smart series 25ts54 c122. A part on the board has burned up (It's blue-green and assuming it's a capacitor) the position on the board it C506. Unfortunately it burned up enough I can't get any details from the piece. The TV started to smell funny and then smoke started coming out so they unplugged it. Later when they plugged it in, it wouldn't turn on but was making a quick ticking sound and then started smoking again. I removed the burn part and the TV now turns on and works without smoking. Obviously the parts there for a reason and would like to replace it but I don't know exactly what c506 is. Any help would be appreciated. I was told that the C506 was a 820pf 2kv capacitor and I've seen on other posts that they recommend replacing it with a 820pf 3kv capacitor. So I replaced it and and now the TV turns on and I have sound but now I only get a horizontal thin line. What happened? It was working OK without the capacitor at all and now it won't work with or without the capacitor - just a horizontal line in the middle of the screen. What should I be looking for now??
Solder the leads of the vertical output IC. Should be done on
every repair as prevent maintenance.If that doesn't help,then
scope the vertical signal starting at the jungle IC.Check B+
voltages as well.If good,check B+ voltages at vertical output IC.
Missing? Troubleshoot power supply ... present = replace IC
Use original NAP part # , no generics..........................T.
Note: C506 is a shaping capacitor.When it burns,it usually
does no harm to other components.Also,while increasing
the voltage rating does no harm, I have not had any recall
of the dozens completed thus far..w/820P/2KV........T.
Power Supply diodes are D409 & D410, I think... located next
to flyback xformer = replace both AND IC500 ALL AT SAME
TIME ! Diode = # 483513039052 X 2, IC = # 483520988531
Experience,patience,humility................................T.
I stand corrected and apologize.......C506 in your 25" set is
Part # 483512247584 = 680PF...........However,the fact remains
no harm is done with wrong value installed,certainly not to the
flyback, vertical IC or the horiz output transistor.Similar repair in
Zenith Tv's often shorts a diode and sometimes burns a resistor.
Terry....................................................................................
dismantle,
Where are you at on your repair?......................T.
Sorry..TMI.....C506 and / or what happens in ZENITH TV is irrelevant and inconsequencial.................................Your problem is no vertical sweep now, so...........Please read my last
post on Nov.21.......................T.
Please read my last post on Nov 21.........................T.
D410 may not be correct.....I am trying to direct you to the
source diodes for the + and -- 13.5 v.....check service manual...
Again, replace all three parts at the same time..........T....out.
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Try to replace the original one capacitor with the best original specification. Don't do any experiment it might be damage the flyback of the TV screen.
Hope this will be helpful.
Check the horizontal output transistor, it may have gone belly up. good news is a replacement is only 6-7 bucks.
well, you stated it was working fine without the capacitor, then wasn't working with or without the capacitor, i assumed you removed the capacitor again. regardless, running it without the cap in place can easily fry the transistor. as far as location goes, it should be located on a heatsink near the capacitor you removed, at least it usually is.
how many times is it flashing? or is it just flashing with no discernible pattern?
i have a really stupid question, is there a switch anywhere on that circuit board? will usually either be a small dip switch, a small lever switch, or something similar.
and also, i apologize, i meant the vertical.. not horizontal.. been a long night.. am working on an old fisher 40" projection tv and just repaired the horizontal on it.
if there is a small switch on the circuit board, with the capacitor mounted in place, flip the switch and try the tv again... many tv's have a service switch, these will cause your screen to show a horizontal line in the center of the screen (collapses the vertical circuit).
if it does not, double check any wires you disconnected when you took the board out to solder the new cap in place..
if this still doesn't work, you may want to run it to a repair shop as you most likely lost your vertical drive, unfortunately i do not have a list of all the parts in the vertical circuit for your particular model. if you wish to attempt it however, try replacing IC500, the part number should be TDA9302H. the back of the circuit board should have the part locations printed on it.
check for a part number, i can cross reference it with a similar model at that point. the tda9302h is a 7 pin package, you can see what it looks like here
although, that would match the description of q502, the horizontal output transistor.
when you turn it on and get the line in the center of the tv is there any movement at all, any color, or is it just solid white with no movement?
well, the c506 is part number 483512247584, the rating is 680pf 10% 2kv.. so the one you replaced it with is highly overrated for the application, it is possible that it discharged and blew something.
as far as checking the transistors, it would take me half the night to type up everything found here
your newest post suggests it could be a loose connection, but i doubt it unless you knocked something loose or overheated an area of the board when you installed the new capacitor.
there are 3 main causes of a horizontal line. service switch is thrown, really bad adjustment, vertical output has a fault.
as far as a schematic, you can try here and grab the chassis 2b service manual, compare it to what you have as it may or may not be the right one.
there is a manual here but it is 23.99 to download
sorry, didnt realize the first manual link was also a pay site. worst case scenario, if they need a replacement tv in time for thanksgiving, you can try craigslist. they usually have loads of people unloading decent electronics at very reasonable prices.
i will be up for another hour or two tonight, and usually check here when i wake up (nice to knock out a few problems before i have to go to work hands-on), so if you need any help i will be around.
i'm not working from a parts list, the force cd shows the 820 value, but the philips component list shows 680 for all 25" models and limited 27" models, partsearch also lists it at the 680 value for all 25ts54c1 based sets.
i dont have a schematic for that particular model, just parts lists without the component locations (unfortunately).
if you are going to troubleshoot it, i would start by removing the board, and tracing the leads from the capacitor 2-3 components in each direction. your most likely culprit is going to be either a blown transistor, diode, or ic.. blown diodes can usually be located visually by looking for a diode with a black line on it that flakes off easily, like dry paint, burn marks on the board, or burn marks on the diode (usually the black line, sometimes it will just look like smoke damage on one end).. easy to replace as well.. transistor testing is a little more involved.. the ic, well.. i have never tested one, just replaced them when it looks like the most likely culprit (amazing how many times that one works) ;)
check the solder connections near the new cap, and anywhere else that may have popped loose, make sure no wires were plugged in reverse, and do a visual inspection for anything that looks smoke damaged or burned.
hope this helps out a bit more, or at least gives you an area to look at...
terryfic makes a good point, on some repairs i have done (my own, not customers hardware) i have used any cap that was laying around and over-rated for the app. as far as i know, all of those tv's are still working fine.
this is aimed at terryfic as well, am i correct in assuming ic500 is the vertical output ic for this model? last night i was working from one of the many binders of parts lists, and while it was listed as such, it looks like you have more experience with this model than i do.
good news, the ic500 part is only 5-6 bux :) the diagram link i posted earlier should give you an idea of what the voltage is and where to check it. now that you know where it is, test it before buying the manual.
have a great thanksgiving, and sorry we couldn't get it knocked out before the holidays :)
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Where is that located and how do I check it? Is that something that may have been affected by replacing the capacitor? Any idea why the TV was working fine without the capacitor once I removed it but when I replaced it - the horizontal line is all I get?
I've also noticed the green led (power on) light in the front is flashing if that helps indicate anything.
I understand - it's been a long night for me too. I'm hoping to get this fixed for my friend before Thanksgiving because if it can't be fixed they're going to buy a new one on sale the day after and I don't want them to miss out on a sale if I can't fix it or buy one when I can. Anyway, I'll check for a dip switch and let you know - What would the part be for the Vertical output transister. I found one fastened to the side rail (not on a heatsink) that is labeled Q503. It's about the size of a stamp with 3 leads. How would I check it if that is the right part?
I didn't find any dip switches and I re-soldered in the capacitor and checked the wires. No luck - still a horizontal line. The light flashes very quickly on and off (no pausing or pattern). Is it possible the capacitor I put in was not right (bad info from another "helper") or is that the right one and am I right in thinking that the 3kv rating is OK just able to handle higher spikes than the 2kv 820pf - or am I wrong. Is that even the right capacitor for c506. Also, how do I check the transistors you mentioned (vertical output) or is that not an issue?
Does anyone have a circuit diagram for this model so I know I'm using the right parts - if not, does anyone know where I could order one?
The line is solid white (originally when it was hooked up to a game system to check the channel/sound etc it was a single rainbow line. I also just realized when I touch or wiggle the Red/White/Yellow (video/audio) input jacks, the line moves from the center of the screen to about 3/4 the way to the top. It doesn't move or change - just a solid stationare line unless I move something - is that a sign of loose solder/connections?
I appreciate all the help so far. Are the numbers you have from a parts list or diagram? The other person on this site Terryfic told me he had worked on several of the same model and the part was 820pf 2kv.
(His response to my original post -http://www.fixya.com/support/t248824-rep...
Also, are there limited components that may have been blown by the capacitor if that's what happened or are the possibilities endless? If there's only a few main components that may be the issue, I don't have a problem replacing them. If so, what all do you recommend I try?
I found the IC500 near the video input connectors and the solder was loose on several of the leads. I resoldered them and tried the TV again. Now the line is a single line of red with a single green line immediately below it and both are near the top of the screen. Wiggling the board and video input area no longer makes the line move so that was part of what I was seeing before - unfortunately - still just a line. If i change the channel, the line gets much brighter white with a fuzzy line just below it that flutters. Also, the green led for power is still flashing on and off quickly if that means anything.
I'm not going to be able to work on it any more before thanksgiving. Thanks for all your help so far. I will probably pay to download a service manual to have skematics and exact lists for this model and then I'll post what I find from there after the holiday. Have a good Thanksgiving and I'll be posting again soon.
Terryfic,
I just got back from the holiday so I'm not any further than I was before. When you say that similar repair often shorts a diode and sometimes burns a resistor - what repair were you refering to - the c506? If so, is there particular diodes or resistors I should be checking and would a shorted diode or burned resistor possibly cause the horizontal line I'm getting or would that be another issue?
OK, I got a service manual downloaded and it shows -13.5V at pin 4 and +13.5V at pin 2. What should I use as the second location (black lead) to get a good reading of the pin supply voltages (red lead on pin)? If I'm checking it right I get +12.5V on pin 2 and +8V on pin 4.
You said to check the power supply diodes that you thought were D409 / D410 near the flyback. D409 is near the flyback but D410 is half way across the board. Is D410 still the right diode or should I be looking at D409 and another diode along with the IC500 to replace? Also, checking the diodes with a diode setting on the multimeter I get open in one direction and around 550mV drop reading the other way. Are those diodes fine or do I need to remove them from the board to test them? I don't have a place near me to get parts so I have to order them and want to try to get all the parts I need at one time if possible so I'm not paying tons of different shipping costs for multiple orders. I appreciate all the help so far, I just want to be sure if I order that those are the 2 diodes I'm replacing and not that I need a different one somewhere else if D410 isn't the right one.
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