toshiba 42tl515u problems

[Wheelman_60]

Hello!

My father-in-law gave me a Toshiba 42TL515U to fix because there's no picture, no sound, the fan turns on and the green light on the front panel blinks 3 times- pauses- and repeats. I'll be testing for continuity but am I better off saving some time and just replacing boards? I'm thinking power board first...

[budm]

Re: toshiba 42tl515u problems

If I were you when asking for help I would:
1) Up load good clear pictures of the whole back side of the TV showing all the boards to show how all the boards are connected together, the straight shot pictures of each board.
2) Post the Voltage reading of the power supply connector that goes to the main board when the TV is off and when the power switch is activated. Each reading should have pin name and follow by the Voltage reading.
3) Just remember that you have the TV in front of you, the helpers do not.

[Wheelman_60]

Re: toshiba 42tl515u problems

The meter reading is the same with the set off and on.

[budm]

Re: toshiba 42tl515u problems

1) You only show the meter reading the incoming AC feeding the power supply board, you need to test DC Voltages on the two connectors of the power supply board that goes to the main board. The pins of the connectors have the pin nmae to tell you what each pin is for, so you need to qrite down the pin name and follow by the Voltage reading for each pin.
2) You need to get digital meter to get more accurate Voltage readings.
3) How much experience do you have repairing the electronics down to board level, component level?

[Wheelman_60]

Re: toshiba 42tl515u problems

I thought I was doing something wrong there
ty... will get the correct readings tonight.
As you can probably tell, experience is limited.

[budm]

Re: toshiba 42tl515u problems

Parts for your TV:
http://www.shopjimmy.com/catalogsear...shiba+42tl515u
This is not going to be for beginner to repair.

[nomoresonys]

Re: toshiba 42tl515u problems

https://support.toshiba.com/support/...eeText=2941923

[Wheelman_60]

Re: toshiba 42tl515u problems

Thanks for the links. I've ordered a digital meter; going to try diagnostics first.

[Wheelman_60]

Re: toshiba 42tl515u problems

Readings taken off wire harness leaving power board going to main board. Would this mean power board is bad?

[Wheelman_60]

Re: toshiba 42tl515u problems

Upon further research I see that I have 5 V supplying the main board so in fact this may be a bad main board.

[doesntmind]

Re: toshiba 42tl515u problems

I have the EXACT same symptoms, here are those readings. I noticed the BL_ON pin is low like Wheelman_60's

PJ90
Pin# - DESC - Standby - Powered
1 - 12V - 0 - 12V
2 - 12V - 0 - 12V
3 - 12V - 0 - 12V
4 - 12V - 0 - 12V
5 - GND - 0 - 0
6 - GND - 0 - 0
7 - GND - 0 - 0
8 - GND - 0 - 0
9 - 24V_SOUND - 0 - 24V
10 - 24V_SOUND - 0 - 24V
11 - GND_SOUND - 0 - 0
12 - GND_SOUND - 0 - 0

PJ91
Pin# - DESC - Standby - Powered
1 - AC_DET - 0 - 3.3V
2 - POWER_SIG - 0 - 3.3V
3 - POWER_TV - 0 - 3.3V
4 - 5V - 0 - 5V
5 - GND - 0 - 0
6 - 24V_LNB - 0 - 24.6V
7 - GND - 0 - 0
8 - OPTION - 0 - 0
9 - BL_ONOFF - 0 - 0
10 - PWM - 0 - 0

PJ860 (connector to LED driver)
Pin# - DESC - Standby - Powered
1 - PWM - 0 - 0
2 - BL_ONOFF - 0 - 0
3 - OPTION - 0 - 0
4 - GND_LED - 0 - 0
5 - GND_LED - 0 - 0
6 - GND_LED - 0 - 0
7 - 24V_LED - 0 - 24V
8 - 24V_LED - 0 - 24V
9 - 24V_LED - 0 - 24V

[nomoresonys]

Re: toshiba 42tl515u problems

Do you have backlights? if not try unplug powerboard from mainboard, turn tv on see if backlights come on.

[budm]

Re: toshiba 42tl515u problems

I have the EXACT same symptoms, here are those readings. I noticed the BL_ON pin is low like Wheelman_60's

PJ90
Pin# - DESC - Standby - Powered
1 - 12V - 0 - 12V
2 - 12V - 0 - 12V
3 - 12V - 0 - 12V
4 - 12V - 0 - 12V
5 - GND - 0 - 0
6 - GND - 0 - 0
7 - GND - 0 - 0
8 - GND - 0 - 0
9 - 24V_SOUND - 0 - 24V
10 - 24V_SOUND - 0 - 24V
11 - GND_SOUND - 0 - 0
12 - GND_SOUND - 0 - 0

PJ91
Pin# - DESC - Standby - Powered
1 - AC_DET - 0 - 3.3V
2 - POWER_SIG - 0 - 3.3V
3 - POWER_TV - 0 - 3.3V
4 - 5V - 0 - 5V
5 - GND - 0 - 0
6 - 24V_LNB - 0 - 24.6V
7 - GND - 0 - 0
8 - OPTION - 0 - 0
9 - BL_ONOFF - 0 - 0
10 - PWM - 0 - 0

PJ860 (connector to LED driver)
Pin# - DESC - Standby - Powered
1 - PWM - 0 - 0
2 - BL_ONOFF - 0 - 0
3 - OPTION - 0 - 0
4 - GND_LED - 0 - 0
5 - GND_LED - 0 - 0
6 - GND_LED - 0 - 0
7 - 24V_LED - 0 - 24V
8 - 24V_LED - 0 - 24V
9 - 24V_LED - 0 - 24V

You do not have either BL-ON or Dimming control signals from the main board.

[doesntmind]

Re: toshiba 42tl515u problems

Forgot to mention that the unit fails flashlight test

You do not have either BL-ON or Dimming control signals from the main board.

I do have signals for PWM but forgot to include them. Here is the corrected chart

PJ90
Pin# - DESC - Standby - Powered
1 - 12V - 0 - 12V
2 - 12V - 0 - 12V
3 - 12V - 0 - 12V
4 - 12V - 0 - 12V
5 - GND - 0 - 0
6 - GND - 0 - 0
7 - GND - 0 - 0
8 - GND - 0 - 0
9 - 24V_SOUND - 0 - 24V
10 - 24V_SOUND - 0 - 24V
11 - GND_SOUND - 0 - 0
12 - GND_SOUND - 0 - 0

PJ91
Pin# - DESC - Standby - Powered
1 - AC_DET - 0 - 3.3V
2 - POWER_SIG - 0 - 3.3V
3 - POWER_TV - 0 - 3.3V
4 - 5V - 5V - 5V
5 - GND - 0 - 0
6 - 24V_LNB - 0 - 24.6V
7 - GND - 0 - 0
8 - OPTION - 0 - 0
9 - BL_ONOFF - 0 - 0
10 - PWM - 0 - 164mV

PJ860 (connector to LED driver)
Pin# - DESC - Standby - Powered
1 - PWM - 0 - 164mV
2 - BL_ONOFF - 0 - 0
3 - OPTION - 0 - 0
4 - GND_LED - 0 - 0
5 - GND_LED - 0 - 0
6 - GND_LED - 0 - 0
7 - 24V_LED - 0 - 24V
8 - 24V_LED - 0 - 24V
9 - 24V_LED - 0 - 24V

Do you have backlights? if not try unplug powerboard from mainboard, turn tv on see if backlights come on.

I do not have backlights, when unplugging mainboard and shorting Pins 3 & 4 on PJ91 connector I do not get backlights. How would I go about tricking this unit to turn BL on?

[doesntmind]

Re: toshiba 42tl515u problems

I want to remove the LCD panel in order to test LEDs. This will be the first time removing a lcd from a 3d TV, is their anything I should be aware of before continuing or is it the same for non 3d tvs?

[R_J]

Re: toshiba 42tl515u problems

You are missing the backlight ON/OFF signal so I would leave the panel together, There is likely a problem elswhere and sure as anything, when you open the panel it could get damaged.
If you disconnect PJ90 from the main baord, you should be able to turn on the backlights by applying about 3 volts to the BL_ONOFF (pin02) on PJ860.
You can use a 3v button battery

[doesntmind]

Re: toshiba 42tl515u problems

You are missing the backlight ON/OFF signal so I would leave the panel together, There is likely a problem elswhere and sure as anything, when you open the panel it could get damaged.
If you disconnect PJ90 from the main baord, you should be able to turn on the backlights by applying about 3 volts to the BL_ONOFF (pin02) on PJ860.
You can use a 3v button battery

Thank you for quick reply, I disconnected main board and applied 3 volts to BL_ONOFF & POWER_TV and it resulted in the back lights turning on, as far as i could tell non of the leds are out

[nomoresonys]

Re: toshiba 42tl515u problems

Is this your mainboard? make sure the numbers on the white sticker match. https://www.shopjimmy.com/toshiba-75...main-board.htm

[doesntmind]

Re: toshiba 42tl515u problems

Is this your mainboard? make sure the numbers on the white sticker match. https://www.shopjimmy.com/toshiba-75...main-board.htm

This is my board, the resolution in shopjimmys image wasnt crystal clear but from what I can make out the numbers match

[nomoresonys]

Re: toshiba 42tl515u problems

Looks like several screen sizes will work for this but sold out at about 7 places I looked online, might need to go with one of the repair services that you send your board to and they fix it if they can and send it back, unless you can do it, this shows which models will work. https://encompass.com/item/8421683/T...e0949a,_Main(f