Proscan 40LD45Q 40" LCD TV Help Needed!

[retiredcaps]

Re: Proscan 40LD45Q 40" LCD TV Help Needed!

So if statistically cheap capacitors tend to die at about 2000 hours then I would say between June and Now I was in that range.

See PCBONEZ talk about cap lifetime near the bottom of this post.

https://www.badcaps.net/forum/showpo...30&postcount=7

[cashkennedy]

Re: Proscan 40LD45Q 40" LCD TV Help Needed!

Yes the capacitor FAQ explains it much better then I did, it would last at least 2000 hours if they ran at tha max temperature (85c probably).

Yours were probably not running at that, and quite possibly they are capxcon capacitors so they are pretty much lieing about the endurance so the lifetime is meaningless.

I brought up the fact that heat affects their lifetime, not to prove it was bad capacitors but just to explain that heat over time is a bad thing for capacitors, but not to rule out capacitors just because the problem occurs on cold starts only.

You might want to save up around 50-100 dollars to replace the inverters or power board (im not sure what is causing your problems), but that would have a good chance of fixing the issue vs replacing components since no one else has had any luck going that route (assuming you know which board is bad).

[70JUDGE]

Re: Proscan 40LD45Q 40" LCD TV Help Needed!

Has anyone figured out what the problem is with this TV?

Did you get to change out the large capacitor?

Please let me know.Thank You very much!

Tyler

[djluis]

Re: Proscan 40LD45Q 40" LCD TV Help Needed!

Did the guy that buyed the kit with the capacitors fixed the problem?
I am willing to buy the kit but need to be sure that it worked.

[mca]

Re: Proscan 40LD45Q 40" LCD TV Help Needed!

After troubleshooting this problem for a while now I figured out what the problem was. The long use is throwing off the timing control board which is connected to your LCD lamp. This pcb board is located under the sheet metal under your power supply.



This unit was hard to get from Proscan but when I replaced it the tv was fine. This t-con board is not repairable because of the way it's made. I had Joe order me one but they are around $100 if you can even get them for that much.

It was a small price to pay to fix that dam 40" however I still got a free 42" from Proscan for the trouble and they never wanted the 40" back so I wound up with two nice LCD's for $435.00. Better then a kick in the head I guess.

[70JUDGE]

Re: Proscan 40LD45Q 40" LCD TV Help Needed!

Are you saying that you didn't have to replace the power supply?I changed the power supply twice on the one I had.First with a used one,and then with a new one.After changing the power supply both times,the TV worked.I thought T-Con board problems were only limited to strange patterns on the screen,or no picture,not power on problems.Thank You very much!

Tyler

[mca]

Re: Proscan 40LD45Q 40" LCD TV Help Needed!

Are you saying that you didn't have to replace the power supply?I changed the power supply twice on the one I had.First with a used one,and then with a new one.After changing the power supply both times,the TV worked.I thought T-Con board problems were only limited to strange patterns on the screen,or no picture,not power on problems.Thank You very much!

Tyler

The power supply is yes the first thing you should look at, I was told by a few people that the slave inverter board and main cpu board will hardly ever go. I did do the cap replacement on the PSU but when you don't see any noticeable damage to any caps, I will recommend that you assume it's your LCD t-con board. I tried to get my new one from Proscan but they sent me a PSU instead, so I just sold it on scambay cause I had an extra one and ordered one from that guy Joe.

Here is the symptom:

First the tv starts turning off by itself. Then it will do it more and more, then finally it will do it but you'll see a dark fade from left to right. As your facing the TV, the inverter board is on the left side, so what happens is, the t-con board cannot sync up properly to the data bus of the main board, once that happens it tells the inverter to shut down. So unless you see burn marks under your inverter, change it. Unless you see caps bulging and leaking, replace them. If not it's the t-con board.

It will most likley be due to an overheating problem with that board, however like I said it is unrepairable and there are latterly hundreds of resistors on there.

[maciakt]

Re: Proscan 40LD45Q 40" LCD TV Help Needed!

Well my tv was working pretty good again up until about this past saturday. Now it has pretty much been not working since (like 5 days) except I was able to get it to work twice (late saturday night and then again shortly after I took it apart on monday) out of probably 100 tries.

I went for the option to replace the tcon board as I also noticed that samsung tv's using the same/similar tcon board also had many complaints of very similar symptoms. It was fairly simple to get at (need to unscrew the 8 screws of the power supply, move it out of the way, then remove 4 screws for the sheet metal cover to the tcon board). It took me about 45mins to take my tv apart to find out what model board I had so I can get a replacement and put it back together.

My new tcon board came today, i eagerly replaced it, but exact same problem So I am assuming this means either my inverter board or power supply board is bad. Are there any tell-tale signs to look for on either? I didn't notice anything funny on the power supply board. mca says the inverter board is on the left side facing the tv, but I don't see it. Is it hidden under the sheet metal?

One thing to note for anyone replacing the tcon board, to save you some time, the 2 ribbon cables connector just "lifts up" and then you pull out the ribbon. Really simple but unless you have used them before, not very intuitive at first. I played around with the connectors on my new tcon board to figure it out so I didn't damage the cables.

[maciakt]

Re: Proscan 40LD45Q 40" LCD TV Help Needed!

The other thing I noticed about my TV is I must have the first revision of the power supply. Mine says AYL400201 Rev 1.0 2009 09 18 3BS0009014. The white sticker on the heat sink says RE46AY2500-20090929 and it is manufactured by AOYUAN.

[mca]

Re: Proscan 40LD45Q 40" LCD TV Help Needed!

The other thing I noticed about my TV is I must have the first revision of the power supply. Mine says AYL400201 Rev 1.0 2009 09 18 3BS0009014. The white sticker on the heat sink says RE46AY2500-20090929 and it is manufactured by AOYUAN.

OK so after testing and testing and testing, there is indeed an issue with the t-con board. If there is an issue with a power supply pcb itself the caps would show damage.
. But if you see no bad caps, it's the t-con board.

[jseleec]

Re: Proscan 40LD45Q 40" LCD TV Help Needed!

My proscan 40" was suddenly turning off randomly, later it began to fade from left to right and then shut off. I looked at the back of my inverter board and found a burn mark on the back. I bought a new inverter, replaced it, and the tv still doesn't work. so following the posts here, i bought a new t-con pannel , replaced it, and still no difference. Am I to assume that this is all because of the power supply pannel ?

[70JUDGE]

Re: Proscan 40LD45Q 40" LCD TV Help Needed!

I would have to say it is the power supply.The TV I had would turn on for a second,fade from left to right,and then turn off.I bought a used power supply,and it worked for awhile,but I ended up buying a new power supply,and that has solved the problem for now.I don't know what could have been wrong with the original power supply,and the used replacement.None of the capacitors looked bad.I hope this helps.Thank You very much!

Tyler

[johnrdz]

Re: Proscan 40LD45Q 40" LCD TV Help Needed!

I have a TV with the same problem, left side dark then TV turns off. Before TV turns off i can hear a noise in the PS and the ballast ligth began to blink in the left side of the screen. I hooked a Scope on the big capacitor and the ripple is normal until the noise comes and I can see a big spike noise over the ripple. I connect a 100uF@200V in parallel to the big cap but it blown, I left the blown capacitor for a while and the noise and ripple disappear. I kept the blown capacitor and the TV worked very well! After that I removed the blown cap and the noise came in one second. I check the blown cap and still it reads 100uF.
For me the problem it is the black transformer closed to the big cap I think it is a kind of leakage inductance problem with it, when it happens you can see a big spike voltage on the inducted voltage... any solution or comment?

sorry for my english

[Th3_uN1Qu3]

Re: Proscan 40LD45Q 40" LCD TV Help Needed!

Isn't your primary capacitor 400 or 450 volt rated? Or is your mains 120v. Anyway, just order another capacitor of the same size, capacity and voltage from a reputable manufacturer like Nichicon, Rubycon or Panasonic and you'll be fine.

[budm]

Re: Proscan 40LD45Q 40" LCD TV Help Needed!

You power supply has PFC voltage booster circuit, that inductor is for the PFC. The voltage on that large filter cap will be about 165VDC when TV is plugged in and not turn on yet, it will go up to about 400V when TV is turn on. Since the 200V cap blows up, I hope you did not damage the PFC booster Diode.

[badone07]

Re: Proscan 40LD45Q 40" LCD TV Help Needed!

Did anyone get there's up an running again? I have the same model PROSCAN 40LD45Q, with the RE46AY2502 power supply & T400HW01-V5 A. Turns on, then goes from left to right & off. I'm low DC voltage readings. No caps are bulged. I don't have any burn marks anyplace or on any other board.

Did anyone just try one of the other power supplies, not necessarily for their particular model screen? They all look pretty much the same, at least as far as the DC side goes.

[Shane711]

Re: Proscan 40LD45Q 40" LCD TV Help Needed!

I also have this TV but mine is a Proscan 40LD45QC. So I changed all the Aluminum caps and still not working. Man, what a royal pain. Then I was testing the voltages at the transformer going to the inverter board and I noticed a drop in voltage when I turn the TV on. So I figured it might be those little blue disc capacitors at the 2 transformers. I disconnected both by raising 1 lead off the board and wouldn't you know, the TV is working now. So I need an expert because I am not sure what parts to replace them with. it says 5/ 6KV and I do not know the value.

Also my T-Con board is bad because I am getting all the colors bleeding. I think I can replace the IC Chip on the T-Con board to fix it. IC RM5101

[dick_barton]

Re: Proscan 40LD45Q 40" LCD TV Help Needed!

Post a photo of the cap and someone will advise you.

[budm]

Re: Proscan 40LD45Q 40" LCD TV Help Needed!

'it says 5/ 6KV and I do not know the value'
5pf 6000V. I expect the inverter circuit to go into shutdown if the Ballast cap in nit in the circuit, but at this point I really know as to which cap is disconnected.
Still need to see the pictures

[Shane711]

Re: Proscan 40LD45Q 40" LCD TV Help Needed!

OK, here are some pictures. Ignore the burn marks. Someone before me busted the wire connector and they had the wires pressed into the socket. There was arching and so I just soldered the wires to the bottom of the board.

In the last 2 pictures I am pointing to bottom of where the caps are.

Is a RM5101 IC the same as a AS15-F IC?