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Discussion Starter #1
Ok guys, this is the first amp I've ever installed (out of at least 40) that has done this to me, and I'm at a loss. Here goes:

The amp is a Massive P950.5 completely new in the box (all sealed up.) It was purchased off eBay from a member of one of the car audio forums (not a big eBay company.) I purchased it a couple months ago and left it in the box waiting for the time to install it.

The amp's protect light goes on immediately. This happens even with all speaker leads disconnected and with the RCA's undone as well. The ground appears solid. I am a big proponent of seeking a very solid ground so in this case I used a seatbelt bracket and bolt with ALL the paint ground off it, straight down to the chassis. I will try another ground point tomorrow just to make sure I'm not missing the boat here, but to me it seems strange that I get solid numbers on the multimeter for those connections.

Other than the protect light, I'm getting strange behavior in two other ways. 1., the power LED comes on very slowly but DOES come on, all the while the protect light is on. The manual doesn't state anything about this, since the power LED is supposed to not light up if the unit is in protect. 2., when the car is running, the lights connected to the amp (there is a lit panel at the top) flickers with a pulsating rhythm that changes with engine speed.

Thoughts? Something is certainly wrong, but I'm at a loss as to what.


For reference, this system is -
Pioneer Premier TS-C520PRS components, Pioneer Premier PRS880 head unit running in network mode, actively running the mids and tweets of the 520's off the Massive P950.5 5ch amp. Currently we haven't installed any subs as the box is still underway.
 

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The system should be irrelevant with the speaker leads and RCAs all disconnected.

If you have metered across the ground and the 12V(+) at the amp and seen above 12V, and across the ground and the RTO terminal at the amp and seen above 12V(+), then your amp is des compuesto.

Have you tested those things? RTO wire might be shorted somewhere.

Sounds toast to me, but might as well run out the grounder.

If the RTO voltage is questionable, temporarily jump 12V from the (+) to the RTO and see if it changes behavior.
 

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The system should be irrelevant with the speaker leads and RCAs all disconnected.

If you have metered across the ground and the 12V(+) at the amp and seen above 12V, and across the ground and the RTO terminal at the amp and seen above 12V(+), then your amp is des compuesto.

Have you tested those things? RTO wire might be shorted somewhere.

Sounds toast to me, but might as well run out the grounder.

If the RTO voltage is questionable, temporarily jump 12V from the (+) to the RTO and see if it changes behavior.
 

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Discussion Starter #4
I didn't bother to check the remote terminal, but I'll get it done next time I see the truck, probably this afternoon.

The guy I bought it from is being REALLY stand-up about it, and I am blown away. I still want to prove-out the situation before I call it as "dead amp", but I think in order to do this I'm better off connecting thing thing to my personal car's system and see if it something else.

WTH is des compuesto? LOL.

If the RTO is shorted, wouldn't the new head unit (Pioneer PRS880) freak out and blow something?
 

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RTO OP might have a protect circuit on it to keep returns down :) so it might be cycling.

Rockford had this problem with some Haflers and Pioneers where the HU couldn't keep the RTO voltage high enough for the TO circuit. But it was in like 1988...
 

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Discussion Starter #6
I'm pleased to report this problem as SOLVED. It was the 12V mains, my connection to the battery itself was unstable. I cleaned everything, and tried a new battery terminal and voila, amp ON and kicking!
 

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Discussion Starter #8
I have a meter, but it just didn't show the problem directly. It showed about a volt down, but only when that votage was compared with the batteries alternative terminals (it is a dual terminal one for GM cars.) I'm unsure why, BTW. We futzed with it for hours before coming to a "what if we just checked this" point of view.
 

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Discussion Starter #10
No its a digital multi-meter, the problem was that we were testing late at night and I didn't pay attention to the fact that we were a volt down from the battery terminal back. I didn't bother to check the OTHER terminal connections for what I really needed which was a much more potent connection.

I chalk it up to trying to diagnose something when I don't have my head on straight enough to do it right.

Oh well, all's well that ends well.
 
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