Author Message
plcnut
PostPosted: Tue Aug 18, 2009 10:23 pm    Post subject: hitachi 53f300, dp25h chassis. deflection board problems

I got this tv from a friend after it quit working, I have replaced the power pwb, and I have replaced the flyback as well as all the IC's that are on the heatsinks on the deflection board except the convergence IC's.I also had to replace a zener diode that was shorted(dh08), but now when I plug the set in, I get a blue screen for about ten seconds and then the set will power itself down. I can turn it right back on, but it will only stay on for 3 to 5 seconds and power down again. After doing this several times so I could test voltages, the 115vdc pico fuse on the pwb burned out because the mosfet (QH01) controlling the flyback shorted out. QH01 was receiving about 6.2 volts on the gate, which was way to high. I am kind of at a loss now for what part to replace next, maybe the IH01 which controls the mosfet, but I'm not sure if it is getting the correct signal either. I have read a lot of posts on this forum, but I haven't found anything that seems to fit this problem. Any help would be greatly appreciated. thank you, Jason

Powered by phpBB © 2001,2002 phpBB Group