Did my amp(s) kill the car battery? What is broken?

[Tolem]

I have a 03 Saturn sedan (l200) with the stock alternator and a slightly upgraded battery. My sound system has been installed for 1.5-2 years now and worked flawlessly during that time, until now.

The amps I have are:

-Eclipse PA4212 130W x 2 powering component speakers

-MB Quart RAA 2400 800W x 1 (bridged) powering a Alumapro Alchemy RX12" sub

I dont know when it started exactly (I know everything was working fine last week). What I DO remember is driving down the road 5 days ago and noting mid drive that there sounded like a few faint thumps from the trunk, I thought they were just bumps in the road (and maybe they were). I thought I smelled that familiar electrical component frying smell, but it wasn't very strong at all and maybe I was just imagining it.

Next I turned up the volume because a good song came on and noticed there was no bass. I turned the headunit subwoofer volume control up and down to no result. Frustrated, I disabled the subwoofer and listened to the music using just the component speakers until I got to my destination.

4 hours later I got back in the car and tried the equipment again on the drive home (thinking maybe it was a fluke). No bass still so I just listened to the component speakers on the way home. In retrospect maybe I should have just shut the entire thing off! //content.invisioncic.com/y282845/emoticons/redface.gif.62fdbfe1a101588a808c4cff71bcb942.gif

I got home and inspected the sub amp for a blown fuse, but the fuses were ok. The amp POWER light was illuminated green as normal. No red lights on the amp or anything I could see. I parked my car and shut it off. I should have checked to see if the amp power light went out but I didnt bother to look. Everything has shut off fine for the past 2 years.

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I went out of state and the car sat there for 4 days. I got home today and went to turn the car on but it wouldn't start!//content.invisioncic.com/y282845/emoticons/verymad.gif.3f39c5c2fd57527b671fad3efdfac756.gif The engine tried to turn over but just couldn't complete the revolution. I hooked a multimeter up to the battery and saw that it was dangerously low! I disconnected the main power lead to my amps from the battery and jump started the car. The car works fine.

Where do I go from here? Im deathly afriad of plugging the system back in to trouble shoot, killing the battery again, and then not being able to jump start it a second time- thus killing my only means of transportation. If I miss a day of work I'm screwed.

Is the subwoofer amp the most likely culprit? Can you usually take an amp to a car audio shop and have them run it through its paces to test it?

Also, the Alchemy RX 12 sub is only rated for 500W RMS, but the amp puts out 800W RMS and maybe I had the gains set too high (for over a year now). Could the sub have finally had too much power? I'm not really sure what a blown sub looks like but would I be able to notice it from the outside? I have not opened the sub box to inspect the inside of the sub but it looks okay outside.

Thank you for your suggestions. //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif

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[Enellz 10+ year member]

sounds like your battery was just low, nothing about the amp pulling current seems fishy. Get it recharge or upgrade one or the other, but you gotta watch your voltage.

 

[Tolem]

So plug everything back in, turn the system on, hook the multimeter up to the battery and watch the numbers?

What voltage range is the SAFE zone for the car on and the system running?

It just started getting really cold at night here (from summertime 50degreeF+ temps down to 30degreesF at night) could that have done the battery in?

The battery is a AC-Delco "Professional Series 78-6YR" with 675CCA. Is this a poor battery choice for the amount of watts my amps are pulling? If I were to upgrade what should I be looking at?

Thank you for your help //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[jrwalte 10+ year member]

I don't think it's a bad battery issue - at least not the primary issue. A bad battery doesn't explain the sub amp cutting off and never turning back on. If the battery was going bad causing the voltage to drop too low, the amp would kick on and off and the component amp would go in and out too.

Probably either your sub amp is gone or the subwoofer. If you know someone with an amp/subwoofer, I'd test with their equipment.

Are both amps grounded to the same spot? It's possible the sub amp ground is loose.

 

[jrwalte 10+ year member]

Under 11 volts and things may start turning off. You want to stay over 12 with long bass notes and over 13 on average.

Check the voltage at your amp, too. It will not see the same voltage as at your battery.

 

[Tolem]

Unfortunately I dont know anyone who can help me swap in some test equipment.

Both amps are grounded to the same spot and the ground is secure.

Is there anyway to determine for certain if the sub or amp is blown? The amp power light does turn on (it doesnt flicker on and off, it stays lit), the fuses are NOT blown and the cone of the subwoofer seems intact.

 

[IDSkoT 5,000+ posts]

I don't think it's a bad battery issue - at least not the primary issue. A bad battery doesn't explain the sub amp cutting off and never turning back on. If the battery was going bad causing the voltage to drop too low, the amp would kick on and off and the component amp would go in and out too.
Probably either your sub amp is gone or the subwoofer. If you know someone with an amp/subwoofer, I'd test with their equipment.

Are both amps grounded to the same spot? It's possible the sub amp ground is loose.

This isn't true. A sub amp that pulls more amperes with lower resistance can be fidgety, not to mention quality of the build. I've seen some amps that will stay on down to 9.5volts... and some that won't live lower than 11.

Get a new battery, plug in your system. It should be fine.

If not, then we'll trouble shoot some more.

And to test if the sub is blown, push down on the cone. If the cone won't move, looks like you blew your woofer. To test the amp, simply put your DMM on the out of the amp, if it's producing volts, amp's fine. Also, unscrew your subs, take them out, and put your DMM on each of the coil on the 'Ohm' setting. If the coils have no resistance, you have a blown coil.

 

[FurbiesAndBeans 10+ year member]

Check the resistance on your subwoofer. if it reads 0 ohms, then its blown.

 

[MmatsDude 10+ year member]

do the big 3 and get a new battery