Dead tv polaroid TDA-03211C stopped working replaced the 2 caps still dead

I'm parting out my TDA 03211c Polaroid 32" LCDTV (cracked screen).
parts list at craigslist.org
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Repaired dead Polaroid TDA-03211C

I fixed a dead Polaroid TDA-03211C for my friends. When it failed it had just been turned on and then it went totally dead. This unit is a little over a year old and out of warranty. When I inspected the power supply it was continuously trying to start up but could not. With a Fluke meter you could see some of the DC output voltages rapidly rising and falling, but never getting to normal levels. I pulled the power supply thinking some of the capacitors were bad. Once I had the power supply out I used the Ohmmeter to check for any open or shorted diodes and/or transistors. To my surprise I found a shorted diode! I figured it would be the capacitors (typical failure in switchers), however they looked OK (not leaking goo or puffed out) and the TV is not that old. The failed diode (sorry I forgot to get the circuit designation) is a HER-304 (near the middle of the board with the cathode lead soldered to a small silver colored heatsink). The HER-304 is a 300 Volt, 3.0 Amp High Efficiency Rectifier in a DO-27 package. The DO-27 package is cylinder shaped with axial leads, 0.375" (9.5mm) long and 0.197" (5mm) in diameter. This diode is for the 20 volt source and is connected to one of the secondaries of the transformer. On eBay I found a vendor selling five (5) HER-305 (400 Volt units, better than the original) for $1.25 plus $7.95 shipping. Also I checked most of the Capacitors with a Sencor Z-meter, all that were check were OK. If a Cap. had another in parallel with it I did not check the other. I removed (un-soldered) the heatsink from the board and then the diode from the heatsink. I put it all back together and Yes, under $10.00 in parts (actually a $0.25 part) and a little time and the TV works again! 24 July 2009.

WARNING!!! WARNING!!! WARNING!!! Switch mode power supplies such as this use and generate voltages at current levels that can be LETHAL!!! If you DO NOT know what you are doing, find someone that does or buy a new TV, it is not worth dying for!!!