Sep 14, 2017, 3:37 AM
Post #1 of 5
So it took a surge from a lightning storm and now just blinks a white led 5 or 6 times and then clicks off when I try to power it on. Power supply is a ba21t0f0201 2 ...
philips 50pfl3707/f7 no power after storm
Fuse is good and no bulging caps. Nothing looks scorched. Quick continuity testing produced no shorts or anything obvious. The pins to the main board aren't labeled but there are labeled diag rails that you can put your leads on (3 p-on 12v - j747, j746, j757 / 2 p-on 5v - j758, j759 / 1 all 3.3v - j755 / 2 hot 17v - j706, j799) and they produce the correct voltage when powered on, although the 5 volt rails are showing 4.92'ish (problem?). I pulled the caps in that area. They were low but still within 5% tolerance. It just occurred to me that I didn't measure the relay voltage. I guess I'll go there next. There were also a pair of diodes down in the .3 range that I thought I'd change out. There was one at .2 but after researching it a bit I discovered it was a schottsky diode and that it wasn't an unusual reading. I guess I'll go ahead and test all the resistors for the correct ohms.
What's baking my noodle now is I went ahead and went for the "easy button" and ordered another power board off ebay. As soon as I plugged it in, the screen came on without hitting the power button. I thought ... great .... that was easy ............ until I turned it off. It wouldn't turn back on and no response at all from the power button. If I unplug it and plug it back in, it does the same thing as the first power supply - it clicks on ..... then clicks back off after a few seconds ....... with one exception ......... no blinking white led. If I disconnect it and let it sit for about a 1/2 hour, then I get the screen back ........ until I turn it off.