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So I found an HDTV on the side of the road, brought it home, took it apart, and found the problem. A blown capacitor. So I replaced it with another one of roughly the same value (original was 16 V 470 uF new one was 24 V 470 uF) but it's still not working. As I'm new to this I would seriously love some feedback! I think I burnt the board too much, here are a couple pictures solder jointsnew capacitor

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    \$\begingroup\$ Are any components smelling hot? Always a first pass for me to find faults. (Your nose is quite sensitive by the way.) \$\endgroup\$
    – skvery
    Commented Feb 12, 2017 at 17:28
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    \$\begingroup\$ And by smelling hot, that's AFTER disconnecting the mains before sticking your nose in there. \$\endgroup\$
    – winny
    Commented Feb 12, 2017 at 17:38
  • \$\begingroup\$ Is F2 intact? Can you measure a body diode on pretty much every transistor, IC and diode? \$\endgroup\$
    – winny
    Commented Feb 12, 2017 at 17:39

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I'm afraid it's not so easy.

The fact that you've found a blown capacitor doesn't mean it's the only faulty component, nor even that it's the root cause of a failure that may have destroyed several components. It could have happened that another component may have been the root cause, and then its failure may have propagated down to the capacitor and blown it up immediately afterwards (for example, by delivering a voltage above maximum rating to it).

Each kind of component has its own failure modes. Some devices fail in short-circuit mode and get burned, making their failures pretty obvious. But others may fail in rather silent ways that can't be spotted with a simple visual inspection.

So, if you're not a qualified TV repair technician then your only hope is trying to get a service manual of that TV model (google is your friend) and navigate through it until you detect all failed components and isolate the root cause. Then you will find what's the actual difficulty of the repair, and be aware it can range from something as easy as just having to rework some solder joints, to having to replace an expensive and hard-to-rework IC.

Good luck!

PS: Your replacement capacitor looks like it has seen better times. Did you test it before soldering it in place?

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  • \$\begingroup\$ Yeah the capacitor is working, it's just a bit old. It's the best I could do without driving 3+ hours to a RadioShack ^~^ I'll definitely do some more research on the TV, guess life never makes it easy for ya! \$\endgroup\$
    – Javan S
    Commented Feb 12, 2017 at 18:30
  • \$\begingroup\$ I believe there are internet forums devoted to repairs worth checking out, too. Once you are armed with the service manual, some people in those forums can help with far more targeted troubleshooting suggestions (like "check voltage in testpoint #XX", etc.). \$\endgroup\$ Commented Feb 12, 2017 at 18:37

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