Trying To Fix A TOSHIBA TV With NO POWER 

Steve, the coil is open circuit. Those coils pass the 240vac on both sides. One side is open. On resistance, you should see roughly a short through each side. The thermistors are probably ok. The coils provide some filtering of noise from or to the mains supply. Also, have you ever heard of a dim bulb tester? It's a device that allows you to let a controlled amount of current into a device. It would let you connect up the TV or other equipment without blowing the fuse. Basically, it puts a bulb in series with the AC supply rail, and in doing so limiting the current / wattage allowed into the device to the wattage of a bulb. If the bulb shines bright, you are drawing the full wattage of the bulb, if it's dim you are only drawing a small current or wattage through the bulb. Its a way of protecting the device by limiting current flow into a piece of equipment. If you switch out the dim bulb, it allows the full current to flow unrestricted, and a fuse will blow if the equipment has a short on the supply rail. Another device you should be using is an isolation transformer to give you some level of protection from electrocution. Good luck.

Very interesting and with the comical add on which makes it a pleasure to watch. Exciting and brave of you to take this on. I wait for part 2 with anticipation and optimism.

This is the second video I watched and the last! I found a simple single motherboard TV out on the curb, had it apart, had done a hard reset. Following your video I found one of the BIG copper coils on mine had been replaced not neat at all like your sodder fixes! On my way to Ebay with my new cute TV waiting patiently!

Plenty Of Comments already about a possible short which stressed "Burnt Out or open Circuited" that Choke, if there are no shorts across the voltage rails "Voltage Test Points to Ground" The choke can be rewound and soldered to it's original points, make sure the windings are returned to the correct turns if there are 12 turns then make sure you end up with 12 turns.. Check every other board and their Voltage Test points to ground as well before connecting them to the power Board, As the Power board will fail as soon as you connect any board with a short in it's supply rails. The Thermistors on the Power Board I believe should have a specific resistance to them when at room temperature BTW, So I'm guessing they too were stressed out to end up open circuited like they are, They need to be replaced with the correct values before testing or applying power to the Board as they are there for the protection of sensitive components on the Board and all those other Boards

I'm always excited for an adventure when I see you've dropped a new video. 🥳

You can desolder the coil from the board and test it scrape some of the insulation off the coil and/or unwind the coil and see if there’s a break in the coil since you can’t get another part...

I met the channel watching My Mate Vince and now I'm doing a full immersion, I like your style and your embarrassing songs. ... Anyone else think he looks like Russell Crowe's geek brother ??

hi bud pls do not be so hard on yourself you are tring something new can not wait to see what happens next?

This is something different. From what I’ve read TVs are a pain to work on, I’m looking forward to the follow up.

Always use a 100w filament bulb (old type not energy saving or led) in series that way if it’s glows dim it’s ok if it bright there’s a short

Good to watch you attempt to fix this Toshiba lcd tv there Steve but maybe you will in the next vlog - Nice 1 👍

we are only human....no such thing as failure when knowledge is gained!

Like stated, the first winding is the issue, of course i cannot really shove my face to the board to confirm is it. If the fuse blew up with in 10 minutes, then there has been short near the ac. I think you did check the caps so then next in line to check Degauss Posistor - very likely. Horizontal output transistor. Power supply regulator if there is one. Power supply chopper (switchmode) transistor if there is one. Diode(s) in main bridge Main filter capacitor(s).

Did you check the 5 V rail? Standby the TV uses 5 V standby you need to check where the standby voltage comes in. If it’s below 5 V then you know you’ve got a problem with the TV and the power supply.

Grants pass TV repair channel. Dave knows everything about electronics repair, especially TV repair.

Don't forget it's switch mode power supply. Possible shorted fet? Transistor.

That's a pretty good Connery

You need a bigger mat Stez 😂

The power board looks to me to have separate smpu and the best place to start is standby voltage and its circuits.

when you narrow it down to the coils all im thinking is, are both coils the same? if so swap them around and see if you get the same issue that way you narrow down its the coil vs its something else. thats my logic anyhow.

and i would check that relay in the black box board..its a power relay 👍👍

0:01 toshiba tv's common faults , 1st - 5 watts ceramic resistor in primary circuit just after bridge rectifier burn open 2nd - 5 watts ceramic resistor in primary circuit just after bridge rectifier burn open 3rd - 5 watts ceramic resistor in primary circuit just after bridge rectifier burn open

I stopped messing with TVs years ago, they blew my mind a lot, the common faults got boring. Anyway Brother since when did you gain the Monty python Patreon. Blowing a fuse when replaced, the first check should be the Bridge, Diodes, MOV's but.. as its a To-Shiba TV it's 2/3 common faults with their shit psu boards. Some comments, are sort of close but no cigar, if it was the spark gaps going off. I'd say replace the caps & no! it's not them Yet! To be continued... 📺 🖖👍

When my friend gave me a TV last weekend saying if I can fix it, it's mine to keep, I admit to thinking "I hope it's something simple, 'cos I'm going to be in over my head. 😬". I can confirm however: T# fuses are time delay, so they resist for a while before blowing (as opposed to F#, which are the more common fast blow). ✔️ Thermistors are thermal affected resistors. ✔️ No idea how to test them, like you say, because they change with relative heat. I agree that Flib and Fuzzy are plausible with the coils. Not knowing much about the internals of a TV, I wonder if there are two near identical circuits to run alternate TV lines in the screen for each refresh (if this theory isn't clear, check out episode 3 of my "Electronics For The Lesser Knowledgeable" series which covers TV and region compatibility). Just a theory. Worst case scenario, you could claim to be a rockstar and launch the telly out of the window. 🤘😂 (Don't do this, kids - it's dangerous and irresponsible. Plus it doesn't spectacularly smash like the old glass fronted CRTs, like the Who would've had... I mean, don't do that either. Can anyone lend me a shovel for the whole I'm digging myself into?...).

Can I ask where I can get one of those mini thermal cameras?

Just a question, I have an Philips blu ray player that won't turn on, it has 5V standby but it's missing +5v and +12. Are this voltage always available or only if there's an enable signal?

im a year late , sorry I only just saw this video. at a pinch you could bypass that faulty filter coil with wire (not the best solution but it'll work), best solution is replace the coil with a new one

I think those RV components are varistors.

Great video, although what does 'haitch' mean ?

1st class video to watch thank you take care kind regards from me kenneth

Is there a part 2?

Do you need the all spark to bring the transformer back to life

Usually on the circuit board, it prompts you where to probe your tester and it tells you the voltages it should be serviced as sadly they don’t do schematics for new TVs. Anyway old televisions. Yes new TVs no

bad connection in the coil

Aaaah, don't you just love a cheap thermal camera 😌 (UNI-T UTi260B)

So what you're looking at is a toroidal common-mode choke. Basically it's a filter that removes high frequency noise from the AC lines, but lets your 50Hz through. As others have commented, something else has died on the board and fried this and turned the fuses into fireworks, so that needs to be fixed first ... so pull the bridge rectifier and check for shorts on the DC side. Test the rectifier while you've got it out. Solder wick those big power transistors and diodes removing them complete with heat-sinks and test those out of circuit too. Finally, you worried me little when testing with AC, it may just have been the camera angle but it did make me squirm a bit. Learn about the one-hand rule, if you get zapped on one hand it'll smart but you'll live, if you short the mains across your ticker it's game over. www.eevblog.com/forum/beginners/one-hand-in-pocketbehind-back-when-measuring-mains-voltages/

Love your vids!

excellent and entertaining

Welcome to the Rock

Please please please steve never ever use both hands when connecting to the home power source like the 240v as you risk is passing between your arms and ofcourse through your chest always use both leads from the multimeter in 1 hand. Really reduces risk of fatality.

PD Pre Dave

NEVER SAY :I don't fix TVs" It is dangerously weird how so many will show up afterwards.

Trying to fix a Toshiba with no power. Me: Plug it in duh. *doesnt work* Me: Well shit, I’m out of ideas

your method is unorthodox but, it didn't friggin work this time Stezza!!

Looks like u need a bigger mat :)

I also in the same problem enjoy playing with TVs only I have inexperience )) =%

its a fault in a winding . i had a similar problem with a VIVO tv bad winding job

I work a small device in the bedroom

Use dim bulb tester, this will protect the circuit and fuse! The bulb will light up when there is a short!

i had a tv with a broken volume button was going to get it fixed but my mom passed so i got hers

I got electrocuted trying to fix one of these. Fun times.

Get on with it, the TV shop I did my apprenticeship at, you would be given 1/2 an hour to get it going, before the boss came over with words of wisdom., and you could imagine what they were.

Why don't you just order another power board whatever that's called so what is the whole board be done with it

5 voltage standby you check

12:17 Why don't we go get a schematic then? Unless Toshiba are one of these companies who copyright all their manuals and won't let anyone see them...APPLE !

Your friend shouldn't be embarrassed for his soldering skills, he should be embarrassed that he bought a POS from toshiba

FAILURE!!!!! Lolol jk. At least you’re trying it.

It’s a Toshiba TV. The best way to deal with this is the skip and buy a better branded TV

next video: Trying To Fix A Car

Don't buy Toshiba they break down & Toshiba don't want to know after the year is up & you have a fight with the retailer to get a repair

what a waste of time

Cringing every time he put his hand near it

Another great video for electronics advice I mainly use badcaps.net TV forum most issues I can't fix myself I manage too with help of the experts on the forums.

I've been watching your vids daily now, and how quickly your channel is growing is an absolute delight! Glad to know there will be more vids on the way!!

So nice to see some consumer electronics where the back is held on by screws rather than those horrible hidden clips.

My far-too-late commentary. (I have more than 20 years experience with switching power supplies.) The coil is most certainly a common-mode choke for EMI suppression. There must be DC continuity through each coil for the mains to reach the bridge. The small components shunting the coils are likely transient suppressors (varistors). At 240V they will be open-circuit. They are meant to suppress high voltages that can be induced by input surges (lightning strikes on the mains,.etc) as the CM chokes can 'ring' and boost sudden input voltages to insane levels. (Normally there is a single large thermistor in series with the input for inrush suppression.)

What I'd probably do here is maybe replace the fuse, turn it on and hook up a thermal camera. Don't blink, don't look away and don't breathe lol. Just keep watching until the fault shows itself 😁

Those axial components you desoldered are indeed very likely NTCs, probably used for inrush current limiting. I agree with those who recommended hunting for the root cause of that common mode choke/coil to fail open, vs. having it's lacquer melt and short windings. That must have been quite a bit of instantaneous current flowing through that thing. The bridge rectifier is a prime suspect, assuming you can't find any shorts on the DC side once you took it out. Fun stuff!! :-)

I have repaired a few tv's normally I just opt to replace the complete board if I can't see the fault quickly. Hats off to you for trying. I just see you have another video on this will watch that now

Tension mounts :) Interesting I hope you get it sorted. Looking forward to the next installment, and by the way you know and have done a lot more than me with your repairs. Keep up the good work mate!

As Fuzzy electronics says the coil has gone open circuit. But to have gone open circuit a lot of power must have gone through it. That would suggest something major has gone short. If you do get another coil check for shorts before putting any power into the board. It is possible that the short has gone open. But this would produce a lot of heat. My suggestion is take the heat sinks of the components as you may find that there is a crack in the faulty one or it may just crumble away.

Great video! Waiting for that coil for next part. Greetings from argentina

Whilst you could remove and ‘bypass’ the choke for test purposes the fault that caused that choke to fail and then blow the fuse ‘when the TV was on for a while’ needs investigating first, otherwise if the fault is still there then any replacement choke will also fail. Ideally remove the bridge and then check it out of circuit followed by high DC voltage, current- protected injection into the bridge output. High voltage power supplies are not in everyone’s toolkit however. If you have a variac with a light-bulb limiter than that could be connected to the input of the bridge (first remove the coil nearest the bridge). A failure after a time period may show itself by the lamp becoming bright. Circuits that fail after a time period are always the most difficult. A circuit diagram would help (the second ‘non blown’ fuse may be in the low voltage side perhaps pointing to an issue in the high side, one or more FETs or something has failed in the switching circuit).

Who’s your friend? Vince? 😂

Theres one or more other component's that have blown on your board..you could be chasing that *forever* ..your best bet..look for a 2nd hand power board for that TV .. often various models use the same board ....ive done this a few times myself .

I had a Vizio 55 inch I bought in 2017 that went bad last year, I replaced it but never got rid of it, I had a feeling it was an easy fix. Sure enough in September I took it apart, tested the power board and ordered a replacement for $50. Now I have an extra 55 inch TV and actually accomplished something 🤣

Hi, those Coils, is one side Positive and the other Negative?, seems like the 3v AC may be where the other side isn’t passing through the first Coil, may be the Negative side, so you could be right, the first coil has a break in the Negative side. Just a thought.

replace thermistors , u can use the black disc ones same thing, from any tv, but thats gone more than likely a mosfet under one of heatsinks has gone short, common is that a vestel psu..

There are capacitors with their internals melted out of them. The power supply is done. Period.

Lol reminds me of when my brother brought me a tv to repair, it was a nightmare with parts all over the living room floor Damn that is one big remote

Slightly off topic but about Toshiba nonetheless. The POS DOLLAR STORE QUALITY TV 43" Toshiba FIRE EDITION I have has been rebooting every couple hours since I plugged it in. Watching a good movie - POP! - Goes to the smiley with three dots and tries to reconnect. TRIES TO RECONNECT! It can't seem to ever connect back up. Says there's no signal. Everything else in the house is running. Takes 20 - 30 min to get the worthless POS connected again. Couldn't find a signal next to the router. Hmmm. WiFi is strong. TV is phenomenally, conspicuously nonfunctioning. I'm not the only one according to the amount of negative, similar feedback. TOSHIBA SUCKS

My money is on an inverter. (Not watched it all yet)

around 11:41 you can see a residue from liquid on the board when you turn it over near your left hand going down the board and over to a yellow wrapped transformer

You have to run current through them they heat up and reduce their resistance

Your DMM was in AC mode when you were checking a DC circuit

These small 2-pin devices are spark gap protectors and they serve to suppress voltage spikes across the coils of the common mode choke. Spark gaps are OK, the common mode choke is not. Likely the coil is damaged somewhere near the points where the enameled wire is soldered to the pins, and often this can be fixed quite easily and you don't need to replace this component. But I doubt that's the only problem.

When I plug mine in I can hear a click in the tv like it’s trying to power up then another click would that also be a fuse issue?

Great practice checking the capacitor 1st. They hurt. Instead of a quick "tchh" that startles u and ends its more of a "VVVVVVVVVVVVVT!" which can make a grown man cry.(trust me)

Bold move my friend !!!

Did he fix this?

The coil is there as a choke filter on the mains input side. Looks like one side of it is open circuit. Probably burnt the coil when something shorted and also blew the fuse. I think something else has shorted further down. Probably a diode has failed short circuit. I'd be removing the bridge rectifier and testing that as a starting point. It's always best to test them out of circuit.

Open winding!

For repairing CRT TV, LCD TV, & LED TV if you see fuse blow, replace fuse with put light bulb temporary for safety, if you replace with fuse again maybe other components will get broken effect too.

Ok, I saw the thermal tester above. WoW! $394.50 CAN! Ouch! OK, what about that component tester?

My knowledge on electronics he’s on about the same level as yours but all myself and retired I would love doing it as a hobby I found by watching your channel I am learning things through what you are doing I have myself worked on TVs and in the past I have bought TVs that will not switch onAnd with my knowledge I have usually narrowed it down to one board I found it a lot easier in the past to search on eBay for a replacement board these are readily available secondhand I suppose for your channel it’s more about finding the exact problem but with these complicated TVs you usually find on the board there’s not just one component at Fails it’s usually two or three as other people have already said I just thought I would put this up to give you another option you probably already know thank you for your channel which I recently stumbled across look forward to your next videos stay safe

Anyone who works on a TV without an “Isolation transformer” is a bit silly.

Is it just me, or am I seeing a whole bunch of water damage on that board?

looking for a faulty 60" CRT online now

I wonder if he ever fixed this bad boy

I was frightened for you there!