Toshiba 57H81 Rear Projection TV Problem

You need to replace 2 ICs they are big black ICs and will have part number on them ,example STK392-110. Mats has ICs 1-800-628-1118

Greetings,

Power supply cannot sustain / provide juice to the whole system.
If you are qualified to do electronics, check the power supply section, otherwise contact a repairman.

Keep us posted and thank you for using our service.
FixYa for all your troubleshooting needs.

Evidently this is a common problem with Toshiba rear projection TVs. You might be able to get it working temporarily by unplugging it, pushing the power button a few times, plugging it back in, and then turning it on. Most likely your power supply is going out on you, and should be taken in to be repaired.

Temporary solution found here.

most possible cause is failed convergence ICs. Unplug the three wires for the convergence yokes then try powering up the set if it powers up the Convergence Ics need replacement

Solved by resoldering some solder joints!!!!!!!
********
Toshiba Model 57H81 Rear Projection TV - Purchased 11-09-2001

Problem: Toshiba 57H81 Flashing Red Power Light, No Picture/Sound, Blown Fuses F850 + F852

Symptoms January, 2009:

• Upon turning on set I got flashing red power light and nothing else.
• Removing plug for one minute and plugging in results in:
• Audible click, steady red power light for 2 seconds then slow flashing red light
• Pushing power button results in steady red for about 2 seconds then slow flashing red light, no other set activity
• Removing power cord for several hours and plugging back in made no change
• Audible click, steady red for about 2 seconds then slow flashing red light
• Possible related note: Over past several months occasionally the entire screen would flicker momentarily and at other times be problem free for weeks.
• Fuses F850 and F852 found blown

Repairs Made:

• PD0074 DEF/CON Power Board
• There are two main power supply capacitors in this set. They are C-809 and C-810. One their negative lead on the printed circuit board re-soldered leads and nearby contacts. I’m told that because the factory left out a printed circuit board eyelet, the connection will come loose over time. When I called Toshiba customer service they said there was a known solder joint problem causing blinking red light.
• Replaced blown fuses F850 and F852.
• I actually installed a fuse panel on the inside of the cabinet and routed the fuse connections here instead of ordering the special fuses and replacing them on the circuit board.
• Had to use a 5 Amp SLO-BLOW for F850. Fast blow does not survive power up. Get the red blinking light.
• Used a fast blow 2 Amp for F852.
• PD0073 SIGNAL Board
• Re-soldered Q751 + Q752 STK392-110 Convergence Amps
• Re-soldered adjacent pads that looks suspicious

Total Cost to Repair about $10

• Twelve hours of my time over three days to research issue, disassemble set, make repairs, add fuse panel.
• Already owned Service Manual and Circuit diagrams from a different 2004 repair.
• Less than ten dollars at Radio Shack for fuses and fuse panel. Already had wires, etc.
• Some solder. Already owned de-soldering tools, etc.
• Visited both local authorized Toshiba factory service repair facilities. One said repair would have to include replacing Q751 + Q752 STK392-110 Convergence Amps with ST392-180, and realigning set for a total of $500+ and it would be more if they had to order a power board. NO THANK YOU! Other shop said $65 for site visit and $30 to make an estimate that could be applied to repair.

I have a toshiba 55hx70 same problem,repair guy just left said it was the power supply and wasnt worth fixing 350 to 400 dollars The tv is 9 years old and they wouldnt even take it to shop. Its been a great tv firs thing to go wrong.. Wo nder if I could replace it myself???

Unplug the set from the wall for about a minute. Plug it back in and see if it comes back on. If the problem still persists then you have a shutdown condition, meaning a short or missing voltage.
You will need to call a technician to diagnose the source of your problem. If other appliances in the house were affected you may have a claim with your home owners insurance. Good luck

You will need a service manual to troubleshoot the set to be able to find whats going on with it . Its in shutdown mode with the led flashing. A good manual is available at this link.
http://servicemanuals.vstore.ca/

Unplug the TV from the outlet for about 30 seconds. This will reset the microprocessor. Re apply AC and power on the TV. If your lucky the set will come on and play. If not, the red light will start blinking again indicating shutdown. There are many reasons for the set to go into shutdown, but one of the most common cause is failure of the convergence output IC`s. If your TV is in shutdown, you will need to find a qualified technician for proper diagnosis and repair.

You might want to check http://tacpservice.toshiba.com/TACP/subpages/pdfs/TechBulletinsTV2002.pdf the first Item talks about power LED lights Power supply does not start