Toshiba 37CV510U bad inverter

[budm]

Re: Toshiba 37CV510U bad inverter

OK, since when the backlights go out and you still get 24Vdc and BL-ON, then it either the inverter or the lamps then.
I wonder about the condition of the filter caps on the power supply board, especially for the 24V power supply section.

[ntehicks]

Re: Toshiba 37CV510U bad inverter

I have tested all of the caps with my cap analyzer and they are showing good. I am thinking something has to be pulling to much power in the lamp area. When I get home tonight I am going to test the connector from the lamp to ground to see if maybe there is some shorting going on. The brand new inverter after about 30 minutes is so Hot. you can feel the heat radiating off of it.

[ntehicks]

Re: Toshiba 37CV510U bad inverter

so what would you test next? would you tear down the screen and look for black CCFL's or is there a way to test to see if the inverter is pulling to much from the power supply. Or maybe the diodes are leaky. is there a service mode on the tv that would tell me how many hours the tv has run. that would give me an idea if the blulbs have had alot of use.

[ntehicks]

Re: Toshiba 37CV510U bad inverter

Well I did it. I took it all apart. I am amazed at how much carbon has built up on the connectors for the lamps. I cleaned all of the lamp ends and put the tv back together. I have an infrared thermometer coming. that will allow me to see what the temp's are on the different items. The 24 volt transformer is still getting very hot. but the tv is staying on. I also reflowed the transformers and all devices on heat sinks.

[budm]

Re: Toshiba 37CV510U bad inverter

Great job taking it apart.
When lamps get old they will draw more current when too much current draw above the protection set point, the inverter circuit will go into shutdown.
The type of lamps used in your TV are EEFL:
https://www.badcaps.net/forum/showpo...0&postcount=90
Do you see any of them has pink/red glow on the ends of the lamps?

[ntehicks]

Re: Toshiba 37CV510U bad inverter

Great job taking it apart.
When lamps get old they will draw more current when too much current draw above the protection set point, the inverter circuit will go into shutdown.
The type of lamps used in your TV are EEFL:
https://www.badcaps.net/forum/showpo...0&postcount=90
Do you see any of them has pink/red glow on the ends of the lamps?

I wasn't able to run the tv with it all apart. I don't see any pink or red as far as I can tell.

[ntehicks]

Re: Toshiba 37CV510U bad inverter

so the inverter on this model is buried under the main board. should the inverter and 24volt section of the power supply be very hot in normal running conditions.

[budm]

Re: Toshiba 37CV510U bad inverter

I have no idea if it is normal or not, it can be just bad design. Did you try running at lower backlights level (backlights adjustment, not brightness adjustment)? Or have a way to check the TV power consumption?
I know that the 42" Toshiba with power supply that always has failed regulator ICs runs very hot.

[ntehicks]

Re: Toshiba 37CV510U bad inverter

on the back of the TV its rating is 120 volts and 1.6 max amps. I have connected the tv to a Kill-a-watt meter that gives you real time volts, watts, and amps. the tv is pulling .94 amps. so just under an amp.

[budm]

Re: Toshiba 37CV510U bad inverter

That is not that high at all. I do not at this point if heat is the problem or not.

[ntehicks]

Re: Toshiba 37CV510U bad inverter

do you by chance have a power board Toshiba 75011638 (PE0531B)

Yes, we do But, you can easily fix your board for under $10.00 or so. You need to replace 2 voltage regulators and done

where are the voltage regulators located.

Try asking in the forum and I will show you step by step. IT IS SIMPLY NOT FAIR TO DO THIS PRIVATELY

Thank you
Aimee

I was told there is a couple voltage regulators that I need to replace. do you know where those are located?

[ntehicks]

Re: Toshiba 37CV510U bad inverter

not sure how accurate the infrared thermometer is. I pointed it at the heat sink that has the diodes that runs the 24volt backlights and it hit 135. I pointed it then at the inverter transformers and they hit 155.
with the back cover off of the TV I am still getting shutdown about 20 minutes.

[ntehicks]

Re: Toshiba 37CV510U bad inverter

is this the regulator that you were talking about.

[ntehicks]

Re: Toshiba 37CV510U bad inverter

parting out tv