ground to battery???

[Lowridin_Chevy 10+ year member]

right now my amp is grounded to the cab of my truck.....obviously someting is not working rite because my amp shuts off on low hits of bass.....so i look at the groung connection to the cab.i see that the paint is still there. i sand it down and still it shuts off....here is my question...do u think i should just run a wire all the way back up to the neg. end of the battery.....do u think this could be the problem.....if i ran the ground all the way back to the battery what gauge wire should i use..currently it is 8 guage goin to the cab.it is a 350 watt amp if that helps

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[helotaxi 5,000+ posts]

Where exactly on the sheetmetal do you have it grounded? If you can get it very close to one of the bolt that attaches the cab to the frame of the truck, you might have better luck. You still want to make sure that you have a bare metal connection and that your power and ground wires are not excessively long. With only 8 ga (and that should be plenty for that amp) you won't see any benefit in running the ground back to the wire. If you were using bigger wire or had a unibody car with the amps mounted in the trunk instead of a truck then it migh make a small difference, but not with your setup. Make sure that you have good connections all along your power supply path. Try a new fuse. The one you have may not have as good an internal connection as it should. Any bad connections will cause a rise in resistance and a significant voltage drop during high current demands. The drop in voltage will cause many amps to shut off. Good luck.

 

[Lowridin_Chevy 10+ year member]

the ground is maybe at least 1 foot long and it is grounded to the floor of the cab just to the left of the drivers seat. when i got the system i didnt know **** abot em all and i got mine from circuit city and the morons there hooked it up. when i found out my system liked to shut off i went back there to get them to check out the problem u know what they suggested i do...get a **** capacitor for a **** 350 watt amp in a truck which has a big stock alternater to start with....pissd me off when they said it was nothin they could do...i looked at the ground connection and come to find out they didnt even sand the paint off so i did that myself and i could turn my system up maybe one more notch and thats it.....is my ground too long....bad location.....also if this means anything i can turn my system up a little bit more when the engine is actually cranked as opposed to only having it running off the battery........thanx for any help

 

[helotaxi 5,000+ posts]

You've got a bad connection somewhere. The Ground is likely not the problem. I would check the pos wire. It definitely a voltage drop causing the amp to shut off and a bad connection on in the pos wire will cause the problem that you are describing. The reason it will let you go a bit louder with the engine running is the alt voltage is a bit higher, so it has to drop more before it reaches the cutoff threshold.

 

[Lowridin_Chevy 10+ year member]

is the voltage drop caused by the loose connection....it wouldnt be the truck would it....i'll check the connections though

 

[helotaxi 5,000+ posts]

Yes, it would be a loose connection. Check the battery ground wire connection point, too.

 

[Lowridin_Chevy 10+ year member]

ok i checked my power wire connections (there-s only 2 right) and still same problem...i checked ground,remote, speaker wires, and rcas and the same.....are there some wires i'm missing that i should check and what is the battery ground wire connection point?

 

[paikiah 5,000+ posts]

maybe it's not your power at all. Perhaps it's the subwoofer hooked up wrong to the amp. Check to see that your amp can take whatever ohms your subwoofer(s) have been wired to.

 

[helotaxi 5,000+ posts]

The battery ground is the wire that runs from the battery neg terminal to the chassis and provides the return path for all your chassis grounds.

Specific spots to check along the power supply route for your amp: the connection between the power wires (+ and -) and the amp, both connections into and out of the under hood fuseholder, the fuse itself, the pos connection to the battery. If all of those are secure and the battery is grounded properly, then you might have aproblem with a loose connection inside the amp. The best way to test that is to wire up everything sitting on your workbench using a short run from the battery + to the amp and the - straight to the battery as well. If you are still having problems, then either your amp or your battery are bad.

Which gets me thinking...have you checked that your battery is good. A bad or going bad battery can cause the problems that you are describing as well. Did you run the system with the car off and run the battery down or some time in the past leave your lights on and have to get a jump. If so you might have done in your battery. Measure the volatge at the battery with a multimeter with the system on and off and with the car on and off. You can put a load on the charging system without using the stereo by turning on the lights. The voltage shoudn't drop hardly at all with the car running and only a tiny bit with the car off. If you are getting a large drop, then you should take your car to AutoZone or PepBoys and have them check the battery. You might need a new one. Doesn't need to be anthing special or expensive, just functional.

 

[Lowridin_Chevy 10+ year member]

it is an '03 silverado so the batterry is pretty new BUT i got the '03 when the '04 started coming out so i could get the big rebates so the '03 might have been sitting out in a lot for a while like maybe 9 months.....could that hurt a battery as well....for real though man thanks for all the help

 

[helotaxi 5,000+ posts]

As paikiah said as well, double check to make sure that the sub and amp are wired together correctly. What sub and amp do you have and we can help you make sure that it is right.

 

[BallerKirb112 10+ year member]

Make sure the ground connection is tight. If your amp is turned up too much. The amp will cut out. This is called clipping. Check to make sure the bass boost and the gain are not turned up too high.

 

[Lowridin_Chevy 10+ year member]

the gain is a hair past half way so thats not the problem....i have 2 sony xplod svc 4 ohm subs wired in parallel for a 2 ohm load on the amp so that rules that out...i dont see a bass boost on my amp so not real sure on that one.....i double checked all the connections at the amp and the battery...so maybe it is the battery. need to go check that out sometime....any more ideas

 

[helotaxi 5,000+ posts]

What amp is it?

 

[Lowridin_Chevy 10+ year member]

alpine mrp-m350 mono amp....really a good little amp i jus wish i could use it to its full potential