Mitsubishi CT-28AV1B LED flashes red then green then goes off and set dead

As you seem to know these sets are plagued with problematic caps. Although one can change loads and still not find the culprit!. I would scope each supply rail to check its smooth as this is probably the most likely route to find whats throwing the prot cct. Is the 8v rail ok- I seem to remember probs with its reg. Plus its always worth changing the cap in the base feed to the chopper Tr. If you have definitely eliminated psu rails as the cause - and the primary supply is ok (runs a bulb ok when loptx isn't connected) then ok you have a problem around frame/line, presumably drawing a lot of current. I have also had eeprom corruption that causes a dead set (ie stuck on stby) but yours doesn't sound like that. its not worth doing the initialise data unless you're certain of that though as all eeprom values need setting up. Hope that helps Andrew

Your advice does help alot as it makes me realise that I need to learn a lot more about TV repairs before I will be able to fix this set. You see I'm an ex electrician and electrical tester (domestic comercial industrial ect.) that has now been out of work for a while bringing up a child on my own. So in my spare time I decided to learn about TV repairs, not sure why but it has always interested me to know how TV's work. Anyway back to the subject, up until now I have managed to fix a few TV's with easily found faults, mainly bad chopeer transistors or HOT's and caps. As they have been easily found I have got away with just using my multimeter. I'm not in it for a quick fix or to even use or sell the TV's that I manage to fix, it's more to do with learning a bit more from each set as I go along. I think that it is now maybe time to go onto the next step like you mentioned and buy and learn how to use a scope or learn how to use a variac or series light bulb to help with fault finding. I have also read about using isolation transformers for saftey puposes when working on the primary side of power supplies but am a bit confused about this one as the info was a bit vauge. If there is any advice or tips you can give me from your experience about using this kind of equipment then it would be appriciated. Thanks

OH and I forgot to mention in my first post that there were some syptoms before the set died but as it happened so long ago I nearly completely forgot. first syptom was that the fuse in the 13A plug popped so I replaced it and the set came back on. Once it was back on the sound was fine but there was no picture until gradually over a minute or two the picture started to go from nothing to a very very dark image, infact it was so dark that I could only make out some very dark blurs and silhouettes. After this process of the picture gradually becoming visible over a minute or so the fuse in the 13A plug would then pop again. Being as though at the time I knew absolutely nil about TV's I very stupidly kept replacing the fuse somehow thinking that it would sort it'self out and after about 2 or 3 replacement fuses the set turned to the state that it is in now and trips out into protection mode. It probably would have been a bit easier to find the fault if only I had not kept replacing those fuses :(

Anyway hopfully this info may make some sense to someone more experienced than me.

The switch mode power supplies in use now are generally isolated ok unless you have to fix the SMPS itself, in which case isolation is a good thing.