Samsung 215tw display cuts out

[alexanna]

Re: Samsung 215tw display cuts out - solved

Hello!

I tried with shorter lamps, but could not gather enough of them, only 4 out of 6, and same symptom occurred.

Several users stated that the fix was related to cables of lamps inside the LCD panel.

Since I could not find more then 4 lamps and was getting pretty curious and anxious about this problem I decided to dismantle the panel.

After getting to lamps I discovered same problem as some users mentioned before: two returning lines/wires (thinner wires) were disconnected/desoldered from lamp connector.

I cut away ~0,5 cm of old wire and pulled it form side of plastic connector to make enough of it to be soldered back to lamp.

After doing like this with other lamps I turned on the monitor and light stood on.
I connected the monitor to a PC and left it working for 48 hours with some changeable pictures (screen saver) and with power consumption turned off and concluded that the problem is solved.

Thank you all for putting out yours experiences and ideas about this.
Bye!

After you've done a few of this type of repair you will find it's a really simple operation. But sometimes finding the fault can be difficult.

[kemog]

Re: Samsung 215tw display cuts out - solved

Hello!

I tried with shorter lamps, but could not gather enough of them, only 4 out of 6, and same symptom occurred.

Several users stated that the fix was related to cables of lamps inside the LCD panel.

Since I could not find more then 4 lamps and was getting pretty curious and anxious about this problem I decided to dismantle the panel.

After getting to lamps I discovered same problem as some users mentioned before: two returning lines/wires (thinner wires) were disconnected/desoldered from lamp connector.

I cut away ~0,5 cm of old wire and pulled it form side of plastic connector to make enough of it to be soldered back to lamp.

After doing like this with other lamps I turned on the monitor and light stood on.
I connected the monitor to a PC and left it working for 48 hours with some changeable pictures (screen saver) and with power consumption turned off and concluded that the problem is solved.

Thank you all for putting out yours experiences and ideas about this.
Bye!

[retiredcaps]

Re: Samsung 215tw display cuts out

PS:
Can I use shorter CCFLs from another monitors with mounted (borrowed) connectors (2 wider and 2 normal) from this not working Samsung and test inverter part???

Yes. I have used shorter ccfls for testing.

[kemog]

Re: Samsung 215tw display cuts out

Hello to all!

Very, very helpfull forum.
Same problem as yours (Samsung SyncMaster 215TW) brought me here.

Any progres on the subject? Rasta Beuher?

Mine situation is the same except that I can see pale reflection of Windows desktop (under some angle of view) after monitor is connected to booted PC and on/off button with blue LED (LED light is constant, not blinking) is pressed on the front bezel of monitor. After pressing this button, ~ 10 - 15 seconds, a bright picture of desktop is shown for 0,5 or 1 sec.

After changing all suspected capacitors, I gathered few ideas/solutions:
- bad secondary windings of HV transformers,
- dead CCFL, so that circuit of high voltage is broken and thus turned off,
- or, some of surrounding SMD components connecting inputs and outputs of HV transformers is down (for example small three pins diods/transistors, or smd capacitors or resistors)...


My PSU/inverter board is a little bit different: IP-58130A (NB-20 REV0.2)
Resistance of secondary windings of all transformers is within range of 988 - 991 Ohms. I do not know how to check its inductance (henries).

Please, let reactivate this topic, and help me to narrow down solutions to this problem.

PS:
Can I use shorter CCFLs from another monitors with mounted (borrowed) connectors (2 wider and 2 normal) from this not working Samsung and test inverter part???

[retiredcaps]

Re: Samsung 215tw display cuts out

I'd like to replace it. I haven't found a direct replacement. Can anyone guide me?

Members here have good feedback regarding ccflwarehouse.com. They sell bare lamps, pre-assembled, and pre-housed options.

Call them and they can help you out.

[PineCreek]

Re: Samsung 215tw display cuts out

Following the rich information in this thread I've been fixing a 215TW. Unfortunately, I've been unsuccessful at repairing a failed CCFL assembly. I'd like to replace it. I haven't found a direct replacement. Can anyone guide me? Ref post by almoodie giving equivalent screens with same LCD. My model is LTM210M2 and freelander indicates it has same screen as Gateway FPD2185W and HP F2105.

[Rtech]

Re: Samsung 215tw display cuts out

Have just measured one of these out of circuit:-
With the Black lead on centre the Resistance measurement to the outside pins wass 55k ohmHave just measured the same one,OUT od circuit,as follows :-
Meter on Resistance,black on middle,then approx 55K ohms to the outside pins.
Red lead on middle, then 5.5M ohms.
Using the Diode function of the meter,then, Black on the centre then 0.230 on the meter to each outside pins
Red on the centre then Open circuit,as it should be.

The reason for, getting a reading both ways as you did, is due to the filter capacitors on the output of the diodes,being slowly charged as the votage from your meter is applied.

The B/Lights are turned on and off by approx 3-4 volts ,from the Logic board, which finds it way to the Inverter controller,which then activates the lights,via the output transistors,Inverter transformers etc.

[Rasta Beuher]

Re: Samsung 215tw display cuts out

Thanks!
When black probe is on the middle, the resistance is 160 ohms from the outer pins. When red probe is on the middle, the resistance is increasing starting from 1 Kohm. The results are the same for the two diodes as the pins are common (I tested onboard).
I am confused, a diode shouldn't be non-passing on a way?

If these components aren't MOSFETs, what is commanding BL on and off? There aren't other 3-pins components in the inverter area. Should I check the integrated circuits on the reverse side of the PCB? If so, how can I do that?

[Rtech]

Re: Samsung 215tw display cuts out

for my two MBRIOI5OCT:
a) Increasing value every second, starting from 400 ohms (+200 ohms each second). I used a higher range than 200.
b) 0.5 ohms
c) 159 ohms

The values seems the same for each one.

Unfortunately, the Part code is MBR10150CT,and it is NOT a Mosefet,but a 10amp Schottky Diode,you need to measure again,by putting the black lead of your meter on the centre pin and measuring resistance with the red lead alternately place on the each of the outer pins...then reverse the leads,measure again and advise.

[cman]

Re: Samsung 215tw display cuts out

See this video.

Testing for Faulty Inverter Transformers Tutorial (Part 1)

http://www.youtube.com/watch?v=eNuGWBPRGKA

this video in no longer valid could some explain how test the 6 transsisters. the pins don't appear to be labeled

[Rasta Beuher]

Re: Samsung 215tw display cuts out

Ok, thanks. So the switch off mechanism is triggered if no CCFLs are connected, which happens here. But it doesn't explain the blue arcs, only when no CCFLs at all are connected...

I tried with the 6 transformers and the original CCFLs after replacing the two inverter caps, it didn't change anything: slight creak noise and cuts out.

I followed the onboard MOSFETs testing procedure for my two MBRIOI5OCT:
a) Increasing value every second, starting from 400 ohms (+200 ohms each second). I used a higher range than 200.
b) 0.5 ohms
c) 159 ohms

The values seems the same for each one.

[PlainBill]

Re: Samsung 215tw display cuts out

Thanks for your answer.
The thread about testing is very informative, I will refer to it for other monitors.

So maybe T303 and T306 are quite outside the range, but before ordering it I would like to make sure that it is what causes the problem. I think it's awkward to have arcs when CCFLs aren't connected, when transformers aren't shorted, and that the arcs moves to other transformers after removing the arcing ones, no?

EDIT: I just tried with other spare CCFLs on 4 over 6 plugs after resoldering the 6 transformers, no arcs but the same symptom. Just a slight creak noise in the area of T301~T303, stopping when the backlight goes off. So I think the original CCFLs are fine...

Normally, should the BL work without 6 CCFLs? And without few transformers suspected to be faulty?

No. The inverter controller regulates the total current through all CCFLs and monitors the individual currents through and the voltage across each CCFL. If any of these are out of limits it will shut down. If one or more CCFLs are disconnected the remaining CCFLs will have to carry more current (so the total current will remain the same). This trips the over current protection.

PlainBill

[Rasta Beuher]

Re: Samsung 215tw display cuts out

Thanks for your answer.
The thread about testing is very informative, I will refer to it for other monitors.

So maybe T303 and T306 are quite outside the range, but before ordering it I would like to make sure that it is what causes the problem. I think it's awkward to have arcs when CCFLs aren't connected, when transformers aren't shorted, and that the arcs moves to other transformers after removing the arcing ones, no?

EDIT: I just tried with other spare CCFLs on 4 over 6 plugs after resoldering the 6 transformers, no arcs but the same symptom. Just a slight creak noise in the area of T301~T303, stopping when the backlight goes off. So I think the original CCFLs are fine...

Normally, should the BL work without 6 CCFLs? And without few transformers suspected to be faulty?

[retiredcaps]

Re: Samsung 215tw display cuts out

only one second backlight, with LED still blue.

Here are the readings of each transformer (1st / 2nd ohms):
- T301: 0.5 / 916
- T302: 0.5 / 937
- T303: 0.3 / 884
- T304: 0.4 / 921
- T305: 0.5 / 910
- T306: 0.3 / 903

1) 2 seconds to black can be

a) bad caps
b) bad inverter transformer
c) bad ccfl and/or wiring

All are discussed in more detail in posts #13 and #14 at

https://www.badcaps.net/forum/showthread.php?t=10419

2) PlainBill suggests that the readings for the inverter transformers should be within 3% of each other at

https://www.badcaps.net/forum/showpo...7&postcount=18

3) T303 and T306 would be outside this 3% range if we use 937 ohms as the reading. 937 x 0.97 = 908.89.

4) And your English is fine.

[Rasta Beuher]

Re: Samsung 215tw display cuts out

Hi everybody,

I just get a T215W, with the symptom described many times here: only one second backlight, with LED still blue. So I thought of an inverter failure, I hoped leaking caps; it wasn't that.

Reminder: https://www.badcaps.net/forum/attach...7&d=1266529707
https://www.badcaps.net/forum/attach...8&d=1266529707

I read with attention this thread, but I think my problem is quite different. Without being connected to the logic board, the primary voltages seemed fine. Here are my experiments:

- With connection to logic board but not to the CCFLs, I have blue arcs with sound on T302 transformer, C302 and CN4... I thought T302 was shorted, but I haven't much experience in transformers.
- After T302 removal, I tried again: blue arcs were on T301...
- I removed T301, tried again: quite big arcs between T304 T305 T306 and CN5 CN6.
- After T305 removal, a smoke came from CN6, and the plastic of the connector started to burn... Of course I turned it off immediatly. Not to much damage I think.

With the help of this, I understood P1 and P2 is the primary winding, S1 and S2 the secondary. Am I right? Here are the readings of each transformer (1st / 2nd ohms):
- T301: 0.5 / 916
- T302: 0.5 / 937
- T303: 0.3 / 884
- T304: 0.4 / 921
- T305: 0.5 / 910
- T306: 0.3 / 903

So, different questions came to my mind:

1) If the problem (I mean electric arcs) moves to other transformers when I removed them, does it mean that the problem is before on the line?
2) The arcs get bigger with less transformers: is that logical, because more current go through the remaining transformers?
3) I listened to the monitor before disassembly, I didn't ear the electrical sound: are there likely arcs when the CCFLs are plugged? I am afraid to damage them if I try that now only with the remaining transformers...
4) The transformers readings seem good, can I be confident on their good working condition?
5) Is there a reason to check CCFLs solders even if the symptom is the same when they aren't connected? I would prefer not to dismantle the panel.
6) Last but not least: ... what to do next?

Does someone have an idea concerning all this?

Please excuse my spelling mistakes, as you noticed I'm not English.

Thanks!

[Rtech]

Re: Samsung 215tw display cuts out

A very Happy Birthday then/

[billb]

Re: Samsung 215tw display cuts out

Great discussion! - my monitor started flickering, then only lighting up for 0.5 sec so I replaced the PSU caps - still didn't work - I just re-wired one CFL (wires were brown and broke off when I pulled!) now my monitor is back in action!!!

Wouldn't have thought to look at the CFL if this forum hadn't prompted me.

good job, thanks all, I am very happy now (and for a bonus, today was my Birthday!)

[greens]

Re: Samsung 215tw display cuts out

I'm glad your monitor is working. Good find on the transformer for 1/2 the price of the other place.

icdparts.net also wanted $15.99 to ship to UK, so it would of cost $28.98

[retiredcaps]

Re: Samsung 215tw display cuts out

The transformer I used was a T51.0007.212 which I got from http://www.aquaphoenix.com/applicati...ex.cgi?item=64 as it only cost $5.99 including first class post

I'm glad your monitor is working. Good find on the transformer for 1/2 the price of the other place.

[greens]

Re: Samsung 215tw display cuts out

First id like to say hi to you all

I have the same problem as "almoodie" When I turn the monitor on the video displays for a couple of seconds, then the screen goes blank.
Power light glows continuously

all caps look ok, then I found one of the solder joints on the bulb has failed within the rubber sleeve .
I resoldered the bulb,
now when I power up I get 5 lamps working perfectly, did tube/transformer swaps and found it to be the transformer.

the problem now is I cant find a SPI 8TP0010 transformer, anyone know I can get one form?

Thanks

Update

This monitor has been in bits for over 12 months, but now thanks to this forum my monitor is now working perfect again

The transformer I used was a T51.0007.212 which I got from http://www.aquaphoenix.com/applicati...ex.cgi?item=64 as it only cost $5.99 including first class post
I had to modify the legs but I had no problems

and I would like to say thanks for the great posts on this problem and thanks to retiredcaps for your help

Thanks again
Greens