Toshiba 55TL515U - 3 Green Blinks But No Picture Or Response

[Howard's Dead Toshiba]

Hello everyone. My name is Howard and I have an older Toshiba (55TL515U) that decided not to work anymore and I'd really like to bring it back to life. This one was kind of special in that it has 3d capability with passive glasses - kinda neat but more of a party trick. Anyway, while I'm fairly mechanical, and have assembled several computers (motherboards, sound and video cards, etc) I am not experienced in TV repair, but I'd like to try to diagnose what went wrong and hopefully repair it.

For starters, can anyone provide some guidance as to a step-by-step approach to diagnose where the fault lays? I have a multimeter and grounding strap ready to go

[nomoresonys]

Re: Toshiba 55TL515U - 3 Green Blinks But No Picture Or Response

probably start there on testing voltages, see what you have, what exactly are the symptoms? https://www.youtube.com/watch?v=XH9GfkGQX1I

[dskall]

Re: Toshiba 55TL515U - 3 Green Blinks But No Picture Or Response

Start with good pictures of boards and connector from power and main board.

[Howard's Dead Toshiba]

Re: Toshiba 55TL515U - 3 Green Blinks But No Picture Or Response

Thanks for the helpful starting info guys. I'm going to try to get started on it during the week, since tomorrow is Mother's day.

[Howard's Dead Toshiba]

Re: Toshiba 55TL515U - 3 Green Blinks But No Picture Or Response

Hello guys, (and/or gals)

Ok, I got the rear panel of the TV removed and took pictures of the 3 boards that I see. I hope I'm adding the pictures correctly, so please let me know if I need to change how I'm attaching them. For some reason, most are showing up 90° out of rotation, but when I click on them, they are corrected. Not sure what I did wrong?

I don't know too much of what I'm looking at, but I don't see any burned or strange features and all the capacitors appear to be 'bulge free'. The only concerning thing I notice is the fan on the right side (green) board is loaded with dust so I will clean that first thing.

What should I check next? (and maybe a tip or two as to how to accomplish the task would be great )

EDIT - I forgot to state what the symptoms are. When I turn on the TV, either by remote or the bottom button, the green power light blinks 3 times, pauses, then another 3 times, then solid. I *think* I see a slight flicker as if the screen is turned on, but nothing appears and I can't get a response from the menu button, nor any input signal. It's as if the TV is off. I can turn the tv off and I hear a click, but I *thought* I remember the green light changing to red - which it does not do now.

Thanks

[dskall]

Re: Toshiba 55TL515U - 3 Green Blinks But No Picture Or Response

In a dark room, turn tv on and press menu button and with a flashlight see if you can see any image on the screen. If not tap on screen and see if you see light flash where you tap.

[nomoresonys]

Re: Toshiba 55TL515U - 3 Green Blinks But No Picture Or Response

ok, get all that dust out of the fan, then try the tv, good place to start.

[lotas]

Re: Toshiba 55TL515U - 3 Green Blinks But No Picture Or Response

Check these capacitors for swollen caps.

[Diah]

Re: Toshiba 55TL515U - 3 Green Blinks But No Picture Or Response

ok, get all that dust out of the fan, then try the tv, good place to start.

+1
its funny the location of the FAN. i think there are missing metalshield which cover main IC and it go under the fan.. other wise what will the fan do..

[nomoresonys]

Re: Toshiba 55TL515U - 3 Green Blinks But No Picture Or Response

it is rather weird, it's just a fan, there's no chip under there or nothing, guess they just wanted to circulate that hot air a little? at first I thought it might be trying to cool off one of the chips but nothing under there.

[nomoresonys]

Re: Toshiba 55TL515U - 3 Green Blinks But No Picture Or Response

ok, here's testing powerboard voltages, there's little legends/maps nearby to tell you what the voltages should be, power tv on and check ALL the pins of the 3 connectors where the cables plug in, PJ90, PJ91, PJ860, report here the ones that do not match the expected voltages on the legends. Example of testing there, on this board testing is easy, you only have one row and you can access each pin from the back of the connector, just place the probe carefully on one at a time: https://www.youtube.com/watch?v=TELvc0thP34

[Howard's Dead Toshiba]

Re: Toshiba 55TL515U - 3 Green Blinks But No Picture Or Response

Thanks for all the replies everyone. I didn't get any time to work on it any more today, but I should get some time tomorrow. I'll report back with my findings.

[Howard's Dead Toshiba]

Re: Toshiba 55TL515U - 3 Green Blinks But No Picture Or Response

Hello everyone,

Ok, I powered up the TV, but I can't see a picture of any kind, with or without a flashlight, nor pressing/tapping on the screen.

I'm not sure if this is normal or not, but almost immediately after I plugged it in, there was a click. Then, after I hit the power on button, another two clicks. The green power light just did it's 3 blinks, pause, 3 more blinks and then solid on.

I looked at the 3 caps as Lotas suggested. They look ok to me and here's a pic -


Then I tested the 3 connectors: Edit - Thank you 'nomoresonys' - I measured the rest and updated the chart.

PJ860 -


01 - PWM - 2.63 volts actual
02 - BL_ONOFF - 3.44 volts actual
03 - OPTION - open (no volts nor ground)
04 - GND_LED - Continuity to chassis
05 - GND_LED - Continuity to chassis
06 - GND_LED - Continuity to chassis
07 - 24V_LED - 24.5 volts actual
08 - 24V_LED - 24.5 volts actual
09 - 24V_LED - 24.5 volts actual

PJ90 -
,
12 - GND_Sound - Continuity to chassis
11 - GND_Sound - Continuity to chassis
10 - 24V_Sound - 24.5 volts actual
09 - 24V_Sound - 24.5 volts actual
08 - GND - Continuity to chassis
07 - GND - Continuity to chassis
06 - GND - Continuity to chassis
05 - GND - Continuity to chassis
04 - 12V - 12.03 volts actual
03 - 12V - 12.03 volts actual
02 - 12V - 12.03 volts actual
01 - 12V - 12.03 volts actual

PJ91 -
10 - PWM - 2.63 volts actual
09 - BL_ONOFF - 3.44 volts actual
08 - OPTION - Open (no voltage nor ground)
07 - GND - Continuity to chassis
06 - 24V_LNB - 24.5 volts actual
05 - GND - Continuity to chassis
04 - 5V - 5.1 volts actual
03 - Power_TV - 3.26 volts actual
02 - Power_SIG - 3.24 volts actual
01 - AC_DET - 3.27 volts actual

Yes, this was a lot to type - haha.

Thanks everyone for their help so far.

[nomoresonys]

Re: Toshiba 55TL515U - 3 Green Blinks But No Picture Or Response

just measure them all the same way, meter set to vdc, neg probe on chassis metal ground, pos on each pin.

[nomoresonys]

Re: Toshiba 55TL515U - 3 Green Blinks But No Picture Or Response

.

[Howard's Dead Toshiba]

Re: Toshiba 55TL515U - 3 Green Blinks But No Picture Or Response

Thank you 'nomoresonys' - I measured the rest and updated the chart on the post above.

[nomoresonys]

Re: Toshiba 55TL515U - 3 Green Blinks But No Picture Or Response

ok, I don't know what the option pin is, but everything else looks good, looks like the main is sending what it should and the voltages are what they should be.

[nomoresonys]

Re: Toshiba 55TL515U - 3 Green Blinks But No Picture Or Response

a quick guess is a backlight issue, 11 years is a very long run for led backlights.

[nomoresonys]

Re: Toshiba 55TL515U - 3 Green Blinks But No Picture Or Response

could also be an issue with the ld board that the backlights plug into.

[nomoresonys]

Re: Toshiba 55TL515U - 3 Green Blinks But No Picture Or Response

this is where one of those around 20 dollar backlight testers come in handy.