Question about Phase Linear UPA424CS Car Audio Amplifier

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Phase Linear UPA424...No sound

I recently purchased a Phase Linear UPA424 amp about 2 days ago..I was working on my car, installing the spekers and what not and when i went to hook up the amp to the speakers i had nothing. It worked the day before just fine. I figured it might be the battery but still nothing. The unit is getting power and the green led has light, but no out put signal is comming from the amp.

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  • Chris Einerson Sep 10, 2006

    "I figured it might be the battery but still nothing." <--i charged the battery by the way.



3 Answers

I hooked one of these up in my cherokee a few weeks ago and I wound up having it in for a coulpe days befor I got it working it would work briefly and stop I changed power wires twice before getting it going by using both sides of some 14 ga speaker wire for the + and ground

Posted on Mar 30, 2007


I returned it and got a new problems with the amp after that.

Posted on Jan 15, 2007

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I had the same problem with mine but i had the 224 version first worked nice just for a small system but i just got this one today and i hooked it up to a small sub box how i had the one before and it just dosent work the other one quit beforhand and i thought it just went bad so i figgerd id buy this one but after about and hr n 1/2 of work to show nothing kinda was a depressing moment, ive gone through my wireing about 4-5 times now and drawn it out 2 times on eveything ive done im just lost, ive even tryed diffrent rca and also tryed a diffrent radio and still nothjing tryed messing aorund with settings still nothing its kinda a bummer

Posted on Jan 15, 2007

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Posted on Jan 02, 2017

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Contact Phase Linear directly and tell them you bought a used car that needed to un-hook the battery to fix. You can come up with the rest of the answer right? Let me know if it work. Goodluck.

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