Question about JBL GTO75.4 Car Audio Amplifier

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Cutting out intermittent problem

My gto75.4 keeps cutting out.The blue LED flashes but as it flashes the red LED dims. (like flashing alternatively but not)When i measure the voltage it goes from 12.5v down to 8 then up again & down again & up again keeps alternating.Like the amp is in constant reset.there is a little popping noise from the speakers aswel.Any thoughtsI have checked the battery & alternator & they are fine????????Please help as i'm gonna have to buy another one...

Comment by hardcorefish, posted on Dec 05, 2007

The wiring is fine as i've had the amp running really well for a few weeks with no probs what so ever.Just suddenly started cutting out this evening & I can't get anything out of it now.But i bought it 2nd hand so don't know it's history.Any more thoughts

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Re: cutting out intermittent problem

If the voltage is dropping to 8v, it sounds like there is a problem with either the B+ line or the ground connection. You should also check the voltage across the battery terminals to see if the voltage is dropping at the source.

The amp may be going into protect mode. Disconnect all speaker wires from the amplifier's terminals. Also disconnect the RCA cables from the amp. Does it still go into protect?

Insert a 20 amp fuse in the B+ line and try to power it up. If the fuse blows with no speakers connected to it, the amp probably has a blown channel.

Posted on Dec 05, 2007

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