Toshiba 55H70 55" Rear Projection Television - Answered Questions & Fixed issues

dark spot could be a faulty led. if you put a program on that is in white screen you should see all the leds light up the screen. dark spot will be were the led is not working. if on white screen and they all lite up but still dark around the area, it could be the lcd screen. and could be dying pixels. and try this video https://youtu.be/wlA2rcrAOCs

Sounds like The main power supply regulator section circuit fault. Either it will be a separate board, or the part of main board. Check and replace damaged component/s at its main power regulator [SMPS] section circuit. Contact any service technician. If you wish to get some details; check the site linked here. Pull up older posts. http://electronicshelponline.blogspot.com/ It will be best to replace the power supply regulator board as card basis rather than making "Surgery" to it; which usually will make loss for both money and time. Even though you can make it right, it will cost around an amount equal to the cost of a new board; including the cost of (spare parts + service charge) More to say, most of the spare parts to it will be difficult to get from open electronic spare part market. This is true to most of the flat panel TV power supply boards; irrespective of its brand and screen size. Search the site by type in the "brand name" to your device; [Exclude the model number], in the "Search box at the top right of the display window of the Homepage" to get gathered related posts.

How do you know it is bad? i do not EVER recall a bad ballast on a Toshiba. Likely the generic lamp you used will NOT fire--Toshiba sets are VERY particular about lamps. that--or a bad color wheel.

I have the same set. I have not found any videos online as of yet, but hopefully this link will help.http://www.doityourself.com/forum/entertainment-center-tvs-stereos-vcrs-dvds-8-track-tape-players/296524-broke-toshiba-55h70.html#b

247 is .050 watt15K ohm
404 is 0,25Watt 1K ohm
420 is 0.5 watt 10K ohm
513 is 0.25watt 100 ohm

However if you dont understand them dont play around with them you may end up doing more damage than what you have now. If resistors blow then some other fault has caused excess power to fuse them and that takes knowledge of how to measure the current at each step. Some of these resistors are related to the power board. Getting circuit diagrams from toshiba is difficult Quite often there is a diagram inside the chassis of each model.

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If 3 d looking or colored lines etc on this model listed here it is a convergence problem and fixable.

The tubes could be shut off for a number of reasons- no 200 volts, no filament voltage, no high voltage.set will also blank (cut them off) if a vertical or horizontal deflection problem---things would have to be tested for voltages etc to see what the issue is.

Red power light tries to come on but does not: most likely cause in this case (most common reason) is one of the two convergence chips is shorted.No magic wand here just experience.To prove or disprove this someone would have to locate the two STK-392-110 CHIPS this set likely uses and unsolder both (18 pins each) free from the board----if set comes on with them disconnected one is shorted---picture in this case will look very 3d but it proves one is bad--they are also each protected with a fuse device (does not look like a fuse) which is usually 3 or 5 amp pico fuse.If all this is beyond your ability take it to a shop.Since the average tech can get at and unsolder the chips in under 30 minutes you should not have to wait long for an answer.

I have to presume you are kidding? Remove the less than ten screws with set unplugged and the rear cover comes off.I have to say if you cannot even figure out how to get the cover off, not a good idea for you to be doing whatever inside the TV.

I am more than willing to help but need more information.


If the red power light is just blinking when you try to turn the set on it means the set is in protective shutdown.

The most common cause for this is one of the two convergence chips used is shorted.

I can tell you how to prove if this is the case or not, I have answered a lot of questions here and am highly rated. I never know the skill level of the person asking so try to tell me something:

Can you solder? If I point you in the right direction (only one I know) can you attempt something?

I am here to help and not talk down to you but some people can attempt what I have in mind and others cannot.

In this case it would involve getting at the two STK-392-110 convergence chips and unsoldering both---if one is causing the problem the set will come on with them removed from the circuit and you will have a fairly inexpensive repair.

The more you tell me the better I can help you.

Before you rate this information let me know what you can or cannot do.

SD TECH

This is a common fault solution which can be checked and corrected by you assuming that there is no component failure. There is a high possibility that the components over a period of heating and cooling, tend to bring on a problem of dry soldering. So my advice is to check the set for some loose joints that have played on to give you these erratic shut downs or poor performance.

The best way to check for loose connections is to tap lightly when the set is powered on , If there is change while tapping then it seems that there are DRY solder joints. Remove main plug, the covers - with caution of high voltage, check for dry joints, use a good soldering iron to solder all suspected points.

Sometimes the fault occurs when the set warms up, if so you can simulate the heat using a hair dryer on the suspected areas, try with the power supply, distribution, Processor controller, driver controllers on the A/V related sections. Also the use a FREEZE-IT spray can simulate the components to cool and show up the fault.

Based on the above method you must be able to locate the area of fault and solder the sections. Sometimes large IC's- ones with more pins- tend to have drying in some pins and so cause faults related to the IC's protocol. Have a rough idea of looking into the areas to reduce the time of probing.

Check for tips to look into the SMPS unit with some of my tips:

http://www.fixya.com/support/r5826301-working_switch_mode_power_supplies

Thank you for using Fixya.

The tv board that call the HYPER board nown as the tv convergence board was dying and have problems,but the tv was still used able that why u able to unplug it awhile,replug it back and get it up and running.Now the tv HYPER board known as tv convergence board are totally dead,colors lines R,G,B mis alignments,have colors shadows pictures or 3D pictures for a minute when the HYPER board was still functional for a little bit.Now the tv HYPER board getting no voltages at all,that why ur tv getting only a power LED indication light flashing only.The tv must get it tv HYPER board fixed also known as a tv convergence board.The tv HYPER boad must have it parts replace like 2 STK convergence ICS and some or all of it resistors too.To get the tv up and running again.The tvs shops will cost u like $300-350 for parts and labors.

Hi
A common problem for these is bad capacitors in the power supply, Remove the back from your Tv and look at the power supply on the left hand side.

You will see roughly around 9 x capacitors that are bulged / domed shaped on top usually these are valued at 3300uf 10V any that have bulged or leaked a brown like substance should be changed.
This will cure the problem as they overheat being sat next to a heatsink that gets very hot!
Try and change them for the same 3300uf but a higher voltage.
Hope this helps

The problem is in the power supply.Maybe the capacitor is leak and deffective.Its needed to repair and troubleshoot by the athurized repair technician to replace the deffective parts.

If you still have the manual, look in troubleshooting for "Blinking LED" this is a diagnostic tool used to help determine the problem. It could be as simple as a lamp or it could be the power supply.
This is the link to your manual if you don't have it.


http://www.fixya.com/support/p203662-toshiba_55h70_55_in_rear_projection/manual-5605#


Hope this helps

www.servicemanuals.vstore.ca has the service manual for your model.

Your convergence is out of whack.

This can be caused by a failed convergence IC - or can be adjusted using the Convergence settings in the main menu.

You need to determine whether or not the unit uses a lamp or a colour wheel to produce a picture. I have encountered that 99% of the time the symptoms described means it is a blown lamp. You have two options you can either take the unit to a repair agent to have the lamp removed or you can remove the lower panel of the unit to access the lamp, a lot of the time the lamp can be accessed via a small panel on the side and is contained in the 'lamp assembly' box. Once you have removed the lamp you can tell by looking at it whether or not it has blown, a blown lamp will look just like a light bulb that has blown (only larger) with the filament inside the bulb being shorted, if you cannot see inside the lamp, gently shake it and if you can hear a rattle inside it, the lamp is blown. If this is the case, you will need to contact the local authorised repair agent in order to order a replacement lamp. I hope this helps. Good luck.

This sounds like a hypermodule problem. Check the site www.TvRepairKits.com for a kit to fix it.

your TV is in shutdown mode due to a short. most likely the convergence chips.
Part # STK-392-150 there are two of them...they are difficult to get to, but inexpensive, about $15 each.
if you are technically inclined you can do it yourself, other wise call a servicer, which will cost you in the $350 range.