Toshiba 37RV530U No power

[Jim1590]

This is one of seven TV's I got off of a guy who had a great idea of fixing busted sets then realized he did not know where to start. Only paid $30 for all of them and one had a decent wall mount, so figure I am not losing out on much. Need power cords on 2 more, 1 is a gutted 55" Samsung , and the other 3 will get their own threads.

This TV does not power on. Do not see any obvious bad caps. Volts appear good going to the main board (all around 23-23.5 volts on line marked 24) and volts going to backlight is at 2.2volts when marked 12 volts. The set is powered on, I have a green light on the main board and the digital sound port is glowing red.

Only replacement boards I was able to find are in the UK, not sure if I want to drop 70-75 on a board when the TV ain't worth it. But if I can fix a component on the board itself... that would be great.


Thanks

[newtothis]

Re: Toshiba 37RV530U No power

Pics of boards and chassis

[Jim1590]

Re: Toshiba 37RV530U No power

on the way

[Jim1590]

Re: Toshiba 37RV530U No power

http://www.2shared.com/photo/qGk891Q...ba_chasis.html
http://www.2shared.com/photo/7LLwUCXk/toshiba_main.html
http://www.2shared.com/photo/MNeXEe4...ower_back.html
http://www.2shared.com/photo/TtwY5yO...nnections.html
http://www.2shared.com/photo/ZCkd8LC...wer_front.html
http://www.2shared.com/photo/IUGBGVs...ba_power2.html

[newtothis]

Re: Toshiba 37RV530U No power

DO you get any LED lights on the front of the set? Green or Yellow?

[Jim1590]

Re: Toshiba 37RV530U No power

Just plug in, get 2 sets of 3 flashes yellow lights. Then turns green. Green is solid and turns on and off with power button. The yellow does not repeat until TV is unplugged and plugged back in. I should have checked that first. It should have been right after verifying it is plugged in! Sorry about that and Thank You

[newtothis]

Re: Toshiba 37RV530U No power

the initial flashes of yellow are normal for this set and will do it every time the set loses AC power, It will flash until the remote is usable.

[Jim1590]

Re: Toshiba 37RV530U No power

ok, so the tv thinks it is working correctly, just no image. or at the least, no blink codes.

hope you mean flashes until the ability to use a remote is there cause I didn't get the remote with it! lol

[newtothis]

Re: Toshiba 37RV530U No power

Basically its just as the software is booting up.. after the orange light stops it will turn to solid green which indicates the set is on.

[newtothis]

Re: Toshiba 37RV530U No power

I am having problems with my ZEUS install so I cannot look at the schematics properly.. as soon as I get working I will take a look and see if I can help out.

[tom66]

Re: Toshiba 37RV530U No power

There will be a connector with 24V, GND, etc on it. Check the 24V from there.

[Jim1590]

Re: Toshiba 37RV530U No power

OK, checked all 3 connections.

The top one in the picture(going different direction) and the middle one are values I expected.
24 volts expected give me 23.5 actual

18 volts expected give me 17.6 actual

12 volts expected give me 11.6 actual

5 volts expected give me 4.9 actual

Power Sig is 3.2

The last connector got the following:
Power Protect 3.0
Power Signal 3.2
AC Detect 3.5
Stop Fan 1.4
Power LCD 3.3
Gnd 0
Gnd 0
12VLCD 2.2
12VLCD 2.2

[tom66]

Re: Toshiba 37RV530U No power

Do you see any pin marked "BL ON" or "ON/OFF"?

[Jim1590]

Re: Toshiba 37RV530U No power

Here is the pins and readings

http://www.2shared.com/photo/1otpLRV4/connections.html

[truep]

Re: Toshiba 37RV530U No power

I don't see the inverter. Per cnet it's not an LED, so where is it?

[tom66]

Re: Toshiba 37RV530U No power

Likely mounted on the panel directly, most of these LCD TVs based on LG panels (like this one I believe) came with the inverter attached to the panel.

Jim, try tracing the 24VINV/GNDINV to a board. There's probably a separate cable coming off it for the control signals like BL ON/OFF. A common fault on these panels is the inverter going bad. If it uses a xx490 inverter, you can sub in an xx504 inverter (much cheaper and better reliability.)

[Jim1590]

Re: Toshiba 37RV530U No power

OK, I will expose the other board it is buried someplace under the main. Will post back once I get to it.

Thanks

[Jim1590]

Re: Toshiba 37RV530U No power

http://www.2shared.com/photo/5r0r1tG...ght_board.html
http://www.2shared.com/photo/U3PUoD3...connector.html

The board itself looks pretty beat up....

[tom66]

Re: Toshiba 37RV530U No power

This TV has been messed with. One cap on the inverter has been removed. From memory they are 680u/35V. Replace both using Panasonic FC/FM/FR from Digikey or other sources. (RadioShack NOT suitable!!) Check the fuse, too.

[Jim1590]

Re: Toshiba 37RV530U No power

I have a high quality shop next town over that I can get these from. Can you please point me to the fuse and where should other cap be? I will start looking myself, but maps are nice!

I have no doubt the TV was messed with by someone who either did not know what to do, winged it, or didn't know when to ask for help. But I only spent $4.28 for the set (got 7 for $30) so I didn't care all that much!