CurtPalme.com Home Theater Forum

dturco · Posted: Fri Jul 13, 2012 10:45 pm Post subject:

macgyver655 · Joined: 22 Aug 2007 Posts: 8508

Ok. That's no good. Locate D701 and D703. Should be right there where you were testing.

Set you DMM to AC scale. Clip your red test clip to the diode D701 on the end without the stripe. Clip you neg clip to D703 on the end without the stripe. Turn it on and give me the voltage.

dturco · Posted: Fri Jul 13, 2012 11:05 pm Post subject:

macgyver655 · Joined: 22 Aug 2007 Posts: 8508

Thats no good either. Are you still hearing that 1 relay click you originally said you could hear.

dturco · Posted: Fri Jul 13, 2012 11:12 pm Post subject:

macgyver655 · Joined: 22 Aug 2007 Posts: 8508

I'll be back in 20 minutes. Locate the power supply board, where the AC plug goes into.

macgyver655 · Joined: 22 Aug 2007 Posts: 8508

There should be a relay on that board, M751. Is that the relay you hear click when turning on?

dturco · Posted: Fri Jul 13, 2012 11:59 pm Post subject:

macgyver655 · Joined: 22 Aug 2007 Posts: 8508

Check fuse F751 on that board.

dturco · Posted: Sat Jul 14, 2012 12:07 am Post subject:

120.7 AC

macgyver655 · Joined: 22 Aug 2007 Posts: 8508

Haha, thats not how to test a fuse, lol. Power off, DMM on diode scale, should read short or same as if you held the test leads together.

dturco · Posted: Sat Jul 14, 2012 12:21 am Post subject:

OK I've always tested fuses on both sides with the hot leg on the fuse and the black on a ground point Confused

This has always found a bad fuse for me, if both sides have power the flow was there, if only one side had it fuse was bad.

Anyway I've tested it and it reads short, 0.00 OHMs

Also F-752 reads 0.03

macgyver655 · Joined: 22 Aug 2007 Posts: 8508

Ok. You procedure would work. I didn't know if you were testing across the fuse with power on as you would then be reading through the transformer coil and would not tell you if the fuse was blown.

So, anyways, there should be a connector on that board with 4 wires, Brown, Blue, Red and Yellow. Should be connector J751B.

With DMM on AC, test between the brown and Yellow, should be 120v.

Then test between blue and red, should also be 120v.

dturco · Posted: Sat Jul 14, 2012 12:31 am Post subject:

macgyver655 · Joined: 22 Aug 2007 Posts: 8508

Ok, those wire go to the main transformer. Coming out of that transformer are a bunch of wires. Look for the group going to a 9 pin connector, should be J783A1.

Dmm on AC test between the following wires.

grey and grey = 4.8v ac
orange and orange = 8.8v ac
brown and brown = 8.8v ac
blue and blue = 17.6v ac

dturco · Posted: Sat Jul 14, 2012 12:46 am Post subject:

grey and grey = 4.8v ac >>>>>5.65
orange and orange = 8.8v ac >>>>>>9.00
brown and brown = 8.8v ac >>>>>>>>>>>8.86
blue and blue = 17.6v ac >>>>>>>>>>>>>>>>>36.40

I also tested blue to black>>>18.8

macgyver655 · Joined: 22 Aug 2007 Posts: 8508

That was my next question. What is black to blue and black to the other blue?

dturco · Posted: Sat Jul 14, 2012 12:53 am Post subject:

macgyver655 · Joined: 22 Aug 2007 Posts: 8508

Ok, transformer seems find. What I'm seeing is you should have tested that 36v/ac on those 2 diodes I had you connect to earlier. Those 2 blue wires go directly to the non stripe end of D701 and D703. I would check that again to see if you get the 36v/ac on those diodes. If not then there is a connection problem between the transformer and the main board. I believe there is another board in between.

I'm off for tonight so I'll check back in the morning.

dturco · Posted: Sat Jul 14, 2012 1:03 am Post subject: