Westinghouse LTV 32 Fuse Problem

[navjas73]

My westinghouse ltv, which I use as a computer monitor, stopped working after some sort of power surge (All electronics in the room shut off). I checked the fuse, and it was blown. (5 amp 250 V slow blow ceramic 5x20 mm) At an electronics store an employee suggested I try a gdc 5a- a 5 amp 250 V time delay glass fuse. After plugging in the power cable, the fuse immediately blew. The employee said that the fuse should have worked, and that if it didnt, the tv might have another problem. Should the replacement fuses that I bought work? Does anyone have any other suggestions for fixing the tv?

 

[Mitchekj]

I'd guess you have an internally shorted FET, or other semiconductor, in the power supply section. Only way to know is to troubleshoot it. My first guess would be the main switching FET/xistor, if it's a common SMPS topology.

Even then, there may be even more components that bit it. No way to know without getting it open and taking some readings.

 

[navjas73]

I don't know what exactly to test. Is it worth learning (I'm a quick learner) or should I go to a tv repair store?

 

[shrtrnd]

I agree with Mitchekj, something was damaged in your tv, or the new fuse wouldn't have blown.
It's up to you. You can take the back cover off the TV (make sure it's not plugged-in), and take a look at the components around where the power cord comes in. You may very well see a burned part, and get lucky, ...but that's no guarantee you'll have identified everything that may have blown. You'll probably need to get the tv repaired by a tech, but that's my suggestion if you want to look at the problem yourself.
With no experience in troubleshooting, and no schematics, it isn't all that easy to fix electronics.

 

[(*steve*)]

Much to my surprise, we have talked people through fixing switch-mode power supplies in the past. (And that's initially what I'd suspect to be the problem)

It relies on very good photographs from you, and probably some share of luck. You will almost certainly require some basic test equipment and also take care not to kill yourself (as power supplies can be very dangerous)

The first step is to take off the cover and locate the power supply (shouldn't be too hard -- the incoming mains will connect to it) and take some good photographs of it. Also note if there are any unusual (acrid) smells coming from anywhere or any obviously burnt looking things.