Elo 1525L power board ptb-1218

[BlkSmth]

Re: Elo 1525L power board ptb-1218

There is power all the way to I802, C828 that connects the top portion of the board... just nothing past

[BlkSmth]

Re: Elo 1525L power board ptb-1218

Updated images again

Guys, I could get no readings on 200 ohm from any of them.
I placed the DMM on diode like you stated and here is my findings:

zd801 = 717
d803 = 497
d803 = 500
d806 = 317 <--both directions for some reason

KA3842A / v251c I801 = not sure how to test

A733P / w28 Q806 = not sure how to test

The Q803 was the s0220 SSS 4N60B

[retiredcaps]

Re: Elo 1525L power board ptb-1218

Better images?

1) If your camera has macro mode, enable it to get sharp pictures.

2) Check the glass fuse. A good fuse should be less than 1.0 ohms.

3) Check the bridge rectifier (just below the big cap) for shorts.

4) Check power mosfet (just right of the big cap) for shorts.

5) Aggh. PlainBill's ISP beat me again.

[PlainBill]

Re: Elo 1525L power board ptb-1218

That was clever. You shorted across Q803, the power FET. Possible collateral damage could include D803, D804, D806, I801, ZD801, and maybe even Q806.

The first step would be to check the voltage across the large cap (with power applied). It should be about 1.4 times the AC line voltage.

If you get that, remove power and allow time for the large cap to discharge. Next, check the resistance across each of the diodes I listed. This can be done in circuit. I would use the 200 ohm range on the DMM. Anything that doesn't read > 200 ohms (especially anything that reads < 10 ohms) should be lifted and tested out of circuit. Do the same for the two transistors. Follow that by testing in both directions with the DMM on the diode test function. You should get conduction in only one direction.

PlainBill

[BlkSmth]

Re: Elo 1525L power board ptb-1218

Better images?

[BlkSmth]

There was an issued with this board when I bought the monitor for repairs.
I replaced a 10uf 50v on c814 and a 47uf 25v on c807. I the got a picture on the monitor without backlamps on. (possible ccfl's' bad, no backups laying around atm) There was a clicking going on the board while the inverter was plugged in but I dont hear well anymore, so finding the location was difficult. Well, here is what happened. I got out the DMM and started probing around. Probing a Mosfet 4n60b sss s0220 while just checking for power I shorted pin 2,3 D,S I belive they are. Now thre isnt any power getting to the top half of the board. OUCH! Any pointers? What did I blow?