Pioneer SD-641HD5 staying in standby.

I've been looking at the forums to find this problem I'm having and I'm stumped.

It's state:
It was working fine for the part two years (I got it used, but theprevious owner stated it had no problems with him either) with noproblem what so ever.

About a week ago, I turned my rear projection on and it immediatelywent back to standby. I unplugged it and let it set for some time, andthen plugged it back in, it auto-turned on, and then went immediatelyto standby. Okay, something is wrong I thought. So I pulled the backcover and on the AC board (to the far right if you look at the back ofit, a LED (location D118) was lit up. No other lights I could see.Seeing other posts, I removed the power board and found numerous coldsolder spots. I corrected that problem and then reattached the boardand powered on the set, it went back to standby again immediately. Ilooked again and now I found that besides the led D118 was lit, thepower board had blown fuse FU206, I replaced the fuse and plugged itback in, it blew the fuse again. Checking the schematic, it led me tobelieve that the AMP board was the fault (specifically theSTK392-040s). A suggestion in one of the forums was to remove theSTK392s to see if it blew the fuse afterward. I did so, and I found aton of cold solder joints on AMP board also. I corrected them and thenreattached the amp board with the STK392 missing. It powered up and wasworking, minus the convergence was all jacked. I didn't bother to doanything, so I powered off the set and ordered the STK392 replacements(the exact ones, not generics). When the new ones arrived, I installedthem and then plugged it back in. it went back to the standby lightimmediately, and the LED D118 was lit up again. NO other leds are onany of the other boards. The forums mentioned to check for an led onthe other boards so I looked with the lights turned off in the room.Nothing. I'm baffled on where to go next.

Please help!