Insignia NS-P501Q-10A Power/Clicking Issues

[dodadew]

Well I am at it again. Got a new one that I am looking for some insight into. I have read a few other threads but reallly dont want to throw money at this set replacing random boards when I just cant seem to figure out which one it is. Heres what I have

When plugged in, I hear a relay click (turn on), then 4 lighter clicks, then another louder click (shutting off). During this time, the LED on the logic board lights up, blinks off and then stays on until the final loud click of the relay.
Voltages with everything plugged in are:
Va (should be 55) is @ 27 (pulsing with the soft relay clicks)
Vs (should be 200-215) is @ 1v (pulsing with the soft relay clicks)


With all the connectors unplugged on the PS except main in, there is obviously no click.

With only the main and logic plugged in it clicks when plugged in...on, no more soft relay clicks, and I get:
Va (should be 55) is @ 54.6 (Drains down to single digits right after light on logic board turns off)
Vs (should be 200-215) is @ 209v (Drains down to single digits right after light on logic board turns off)

And lastly with the x-main unplugged from the y main, I get the same as above.
Va (should be 55) is @ 54.6 (Drains down to single digits right after light on logic board turns off)
Vs (should be 200-215) is @ 209v (Drains down to single digits right after light on logic board turns off)

Any ideas on where to go from here? I cant get the power supply to hold VA or VS. The panel buttons work on the front when the X board in unplugged. I have no sound whatsoever. I do not know if this set has a power on sound...but I am not hearing anything with a line in plugged in and pressing the input button. I know it has one buldged cap on the PS, as you can see in the pic...but I pulled it and tested it and it came back at 420uf, its labeled @ 470uf. I plan on replacing those stupid samwhas in there but if need additional parts also Id prefer to buy them all at the same time.

Do any of the combined wisdom here have any ideas on where to go next?

[tw2005]

Re: Insignia NS-P501Q-10A Power/Clicking Issues

Samsung based so maybe search the forum for anything on
PN50B400P3DXZA PN50B430P2DXZA PN50B450B1DXZA or shortened names or even the board numbers for similar issues.

Other thing that could be tried is isolate the main board, jumper the logic board for the test pattern generator and jumper the psu to force it on and see if it comes to if. if so then main board otherwise you'll have to check out the buffers, y and x for shorts.

There may be a troubleshooting guide from samsung on those models I listed which may help.

[Neelix]

Re: Insignia NS-P501Q-10A Power/Clicking Issues

Sounds like the TV is trying to switch on a few times, but detects a problem each time and then gives up. Could possibly be shorted X-main board because only when that board is unplugged, does the VS and VA rise to the correct values

[dodadew]

Re: Insignia NS-P501Q-10A Power/Clicking Issues

I pulled the X-Main and metered some of it. I do have a short somewhere on the right hand side of the board. Any tips on how to pinpoint it rather than desolder until I find it? If I meter across any of the transistors or the 4 large caps I get a dead short.
I cant find the board to just replace it and would rather fix it than replace it.
I did test the power supply with PS to GND and VS to 5 thru a resistor and it turned on and the voltages stayed up and were right where they needed to be. Also with the X-Main unplugged I do get a flicker on the panel.

I assume one or more of the transistors have let their magical smoke out...is that a proper assumption?

[Naturallyk2]

Re: Insignia NS-P501Q-10A Power/Clicking Issues

dodadew, if the cap is below 470uf, you need to replace it. The issue you're describing is exactly what bad caps do to PS's. What kind of meter did you use to test its capacitance?

[dodadew]

Re: Insignia NS-P501Q-10A Power/Clicking Issues

I understand what bad caps do. I intend to replace all those bloody samwha caps. I am glad that I was able to at least test the power supply with nothing connected to get the readings seeing that the voltages were correct. Now I can cross that one off the list. (other than replacing the caps).

[dodadew]

Re: Insignia NS-P501Q-10A Power/Clicking Issues

Well I pulled a few transistors from the shorted X-Main and tested them out of circuit...dead short on 4 of 4 of them. Part RJP30E2. No more shorts on the board with them out. As I can not find this board anywhere now, I guess I will the parts to my cap order and hope I don't toast the new ones putting them back in. Is there anything I could test to see what caused them to die...or do you think it's just the heat / old age that got them.

[Neelix]

Re: Insignia NS-P501Q-10A Power/Clicking Issues

Most likely old age. I usually just replace faulty LG X-main boards and don't try to repair them, but maybe there's somebody else here that have repaired those boards before and can say if only replacing those shorted transistors would be enough or if there is anything else on the board that you must also replace or measure

[Neelix]

Re: Insignia NS-P501Q-10A Power/Clicking Issues

Samsung I mean, not LG

[dodadew]

Re: Insignia NS-P501Q-10A Power/Clicking Issues

I would just replace the board, but I can't seem to track one down anywhere. I saw that a few of them popped up on ebay over the last few months. Now I just have to wait for another one to show. And hope it's not already fried. That's why I'm going through the trouble of repairing this one. Or trying to.

I don't have any more shorts on the board... So maybe I'll just replace them and hope for the best. Before that I'll check everywhere else for shorts.

[dodadew]

Re: Insignia NS-P501Q-10A Power/Clicking Issues

Well I finally got around to replacing the shorted RJP30E2 transistors. Now the set turns on...sound works (no startup sound but I don't know if this model has that)... so that is progress. Now I move on to...what causes the problems shown in the attached picture I rechecked my VS and VA and both are correctly in range. When I disconnect LVDS and jumper on the control board...i get test screens but the picture still does the same thing. Has anyone seen anything like this before?

[dodadew]

Re: Insignia NS-P501Q-10A Power/Clicking Issues

Here is another picture. The whole screen is distorted just like above.

[dodadew]

Re: Insignia NS-P501Q-10A Power/Clicking Issues

What kind of meter did you use to test its capacitance?

Forgot to answer this before... I used my Fluke 177 set to capacitance.

[Nick's Tvs]

Re: Insignia NS-P501Q-10A Power/Clicking Issues

Dodadew you probably have additional bad components on your X-main that you didn't see. Some times the transistors will fail but they will fail with a few k ohm left in them and go unnoticed. You also may have a few surface mount chips on the back side that are bad.
I am saying this because I have this LJ92-01688A X-main out of the same NS-P501Q-10A with the same shorts on the same transistors Q4104-Q4101-Q4302-Q4301 and then additional cracked solder joints on Q4503-Q4504-D4505. So far that seems to be the extent of the damage with additionally a burnt surface mount 5 pin transistor at Q4102. It seems to be the exact same transistor as Q4103 but I don't know for sure and either way Q4103 numbers are faded off. I do believe I am reading 5A on it however.
If anyone could confirm what component Q4102 is, that would be super awesome.

BUDM/TOM66/Anyone knowledgeable, how can I figure this out on my own so I don't keep asking and being dependent on yall? where does one find out exactly what kind of component is on these boards if they are burnt off?

[Nick's Tvs]

Re: Insignia NS-P501Q-10A Power/Clicking Issues

Quick update on my issue, but actually the Q4103 is not the same as Q4102 I didn't notice the extra leg on my board since it was so badly burnt off, but I will upload pictures in a bit

[Nick's Tvs]

Re: Insignia NS-P501Q-10A Power/Clicking Issues

Ok please see attached pictures.
The first 3 are of the top of the board and the components that were shorted. I took 7 out of circuit already, and they had some really bad overheating issues turning the board black around there solder joints. Anyway, then I have pictures of the back. I slowly zoom in on the component that is burnt out, and then again on the same circuit, just on the other side of the board. I just can't read the markings on either of the components due to obvious burning on one, and probably just heat stress on the other.
Any help would be just terrific!
Thanks

-Nick

[Nick's Tvs]

Re: Insignia NS-P501Q-10A Power/Clicking Issues

Ok well PTS electronics, here I come! I will make sure to post the part number of the part when I get it in case anyone needs the info for future reference.
Thanks for trying if you did.

[Nick's Tvs]

Re: Insignia NS-P501Q-10A Power/Clicking Issues

The burned component markings are: Q4102 4.6, Q4103 5K, Q4105 K702K