Toshiba Regza Three Yellow Lights and blowing fuse

[lowteq]

Hello.

I have a Toshiba Regza 42xv545u that I've been attempting to repair.

When I first received it, there were no lights at all on the front of the TV. I worked backwards from the AC in and found that a thermal fuse resister R850 next to the bridge rectifier was open. I also noticed that fuse F820 was missing.

After I replaced R850 I started seeing three yellow lights on the front panel when I hit the power button. According to the manual that means the TV is starting, but it never actually does. I replaced F820 as well and found that it blows immediately, but I still get the three yellow lights.

The power supply board has model number PE0620.

Does anybody have any thoughts?

Craig.

[petehall347]

Re: Toshiba Regza Three Yellow Lights and blowing fuse

did someone remove the fuse ?
if so there is a short ..maybe a fet or 2 . and more damage .

[dskall]

Re: Toshiba Regza Three Yellow Lights and blowing fuse

Start following the traces from F820 and test the components till you find the shorted component or components.

[budm]

Re: Toshiba Regza Three Yellow Lights and blowing fuse

R850 is for inrush current limiter and it is bypassed when the relay next to it is turn on, but if he relay does not come on it will cause the resistor to over heat and go open circuit.
Fuse F820 is for the PFC Voltage booster output for feeding the SMPS IC Q860.
Which revision of YOUR board, good clear pictures of your board will help.
Is it this one?
Toshiba 75013066 (PE0620C) Power Supply
http://www.shopjimmy.com/toshiba-750...pply-unit.htm#

[lowteq]

Re: Toshiba Regza Three Yellow Lights and blowing fuse

Hello

It is the C version of the board. I've attached a photo of the board.

Thank you in advance for any help you can provide.

[budm]

Re: Toshiba Regza Three Yellow Lights and blowing fuse

Check the resistance between the output side of the fuse 820 and the primary side circuit GND (the negative leg of the main dc filter cap).

[lowteq]

Re: Toshiba Regza Three Yellow Lights and blowing fuse

Hello

Thank you for the troubleshooting advice.

I've had some work stuff come up so I won't get a chance to take a look until tomorrow, but I will let you know results.

Craig.

[lowteq]

Re: Toshiba Regza Three Yellow Lights and blowing fuse

Hello.

I've measured the resistance between the output side of fuse F820 and what I believe to be the main filter capacitor (R821 a 150 microFarad, 450V) capacitor. The resistance was 0 ohms, I assume that is bad. I also measured between the other very large capacitor on the board (R820, also 150 microFarad 450V). It was also 0 ohms.

I've noticed there is a repair kit on ebay for fixing a blown F820 fuse on PE0620 power supplies, but it doesn't say what's actually in the kit. Is this the solution to my problem?

http://www.cafr.ebay.ca/itm/Repair-K...-/171547395992

Craig.

[budm]

Re: Toshiba Regza Three Yellow Lights and blowing fuse

The fuse feeds the SMPS IC Q860.
What is the P/N?

[lowteq]

Re: Toshiba Regza Three Yellow Lights and blowing fuse

It's labeled Q860A on the board. The part number is

STR-Z2589
86 10

Craig.

[lowteq]

Re: Toshiba Regza Three Yellow Lights and blowing fuse

I've done a bit more probing around on the PE0620C power supply board for my TV and I'm finding that all roads lead it SMPS IC Q860A.

Should I order a replacement STR-Z2589? Are there any other components I should order with it.

My knowledge is limited but getting a bit better.

Craig.