Samsung HP-T4264 Plasma Easy Repair on Power Supply

[Taterbug]

I purchased a Samsung Plasma HP-T4264 Model Code HPT4264X/XAA off of Craigslist for twenty bucks. The unit would come on for just a few minutes then shut off. I would turn right back on and then play a few minutes longer and shut off again. I examined all of the caps on the power supply board and they looked good, no bulging or leaking. I removed the power supply and examined the solder joints around the heat sinks and IGBT'S associated with them and found the problem which was solder joints that had broken loose on the heat sink in the center of the board and the IGBT's Connected to it. I re soldered all of the bad joints and the TV has been playing great ever since. I am including a photo of the board with the heat sink circled that had the bad solder joints.

[Alastair E]

Re: Samsung HP-T4264 Plasma Easy Repair on Power Supply

Very common to have dry-joints on the devices mounted on heatsinks....

The heat/expansion/contraction on heating/cooling over time stresses out and fatigues the solder--that eventually cracks around the device's pins....

Some models of Sams. destroy the MOSFETS and drive circuits when this happens--Always worth re-soldering with Good Old Fashioned Leaded solder, those connections of things attached to heatsinks....
--The Transformers are also worth checking for similar dry-joints....