IA 20.1 Problem

[TheVille 10+ year member]

Hello, my amp and I have not been getting along recently. The initial symptom was random pops getting thrown into the signal going to my sub. Before too long I took it out to avoid doing any damage to my speaker. Now I have the amp sitting in my lap, poking around with a multimeter and looking for any signs of a short. As far as the electrical connections go, it looks immaculate.

This is where it gets weird. Amp in my lap, guts facing up, power terminals to my left. Rotate the amp 90degrees so that the guts are now facing away from me and the positive and negative power terminals become connected, zero resistance. Lay it back down, if I tap/wiggle the of one of the 2 solid state relays the pos/neg terminal will go back to being an open circuit. Any have any experience with this amp and seen anything like this? Or know of common problems in that area? This makes me say the problem is the relay...but its solid state, no moving parts which should mean my rotating the amp around shouldnt affect it.

Sidenote, it only exhibits this behavior if u rotate it the way I mentioned, other orientations seem not to affect it. I really appreciate any help, I'd like to revive this things, its a champ!

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[mossberg385t 10+ year member]

//content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif that is an odd problem

 

[Spooney 10+ year member]

Is there a possibility that there may be a strand of wire or something in there that is moving around when you rotate the amp? You said you were getting random pops into the sub. Are your rca inputs possibly damaged? Maybe a piece of one of them broke loose and is resting across the power terminals. I think you are going to have to pull the board from the sink to get to the bottom of this.

 

[TheVille 10+ year member]

I suppose its possible....soooo many heatsink screws!

 

[Spooney 10+ year member]

If you do try this its very important that when you go to put the amp back in the heatsink that you make sure there is NOTHING between the fets and heatsink other than the insulator and heatsink compound if it has any. It only takes a very small piece of debris stuck behind a fet to keep it from properly transferring heat to the heatsink and or tear through the insulator and short the fet to the heatsink. Both will lead to failure of the amplifier. If the amp doesn't currently have heatsink compound I would add it when I put the amp back together. I'd be willing to take a look at this for you if you paid the shipping cost.

 

[TheVille 10+ year member]

I finally got the time to sit down and pull out the board. Underside is pretty clean, barely any traces of dust and no immediately noticeable metal flakes/solder balls/strands of wire. I just spent about an hour looking over the backside with a flash light looking for whiskers or other signs of two points being shorted. I can't find anything, and its still exhibiting the same behavior....Might have to send this in to IA //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif