I have a WS 65908........it has the same problum--listed on this site.......power on for 3 seconds...and it said this.... Do the self test this model has: When set shuts off and on front of set power light goes out: Press and hold on the front of the set both the Menu and Input (device) buttons at the same time for at least five seconds and release both....I did this! and the green light..blinked (2) times...then blinked (3) times...it repeted this...So what does this code mean?

Error code 23 on this set means that the Horizontal Deflection circuit of the set has failed. Usually this points to a damaged Horizontal Deflection IC and sometimes the HOT(Horiziontal Output Transistor) as well, not to mention the resistors that are blown when the IC failed. Replacing these parts should resolve the problem.
PS:Note that the Deflection circuit involves certain high-voltage components and prior to repair it is advisable to discharge the high voltage before attempting the repair. You will also need to know how to use a multimeter(to test the HOT and look for blown resistors) and a soldering gun. If you think you can do it yourself, let me know and I will provide you detailed step by step instructions.

Sai.