So today, I took out my freshly rebuilt engine for a ride, and got a check engine light. I went home, and pulled the Qlogic kickpanel off to jumper the ECU. Turned out to just be that I didnt turn the gas cap enough times. But when I went to start it back up, the subs and front speakers in the kick panel werent working. So I went in the back to check the amps and EQS, and one of the amps wasnt powered up. I checked the ground, and retightened the screw holding it to the body, and the amp turned on. But still no sound.
So I checked the other amp, and checked the ground, and when I moved the wire a little, it sparked at the ground point. Then there was some smoke coming from the amp. But the power light was still on. I took it apart, and everything looked ok, just the distinct smell of burning electronics.
My main question, is how can you test an amp to see if it is burnt, or whatever. The amp is a JL 500.1 and there is no internal or external fuse as far as I know.

 

Simple if you let the smoke out then you fried the amp. You have to keep the smoke inside the amplifier for them to work.

Your probably looking at a $100-$150 repair bill.

Honestly if you had smoke comming out of it I wouldn't turn it back on until you get it checked out. Without a fuse you will just cause more damage and a higher repair bill.

If you want to sell it let me know.

 

I took it apart, and yeah, theres some burnt solder spots. If you wanna buy it, let me know, I really dont want to try and fix it.

 

yup if the magic smoke appeared its gone to amp land most likely. i wouldn't ground to the body if all possible. find a seat belt bolt or something else thats at a strong point. if all else fails run a ground to the battery.

 

i thought jl amps had eternal fuses

 

next time ground it better and you may not have this problem.

 

I grinded down to bare metal and bolted the ground to the body. I haven't had any problem in the almost 5 years its been in my trunk, or any of the other vehicles I've installed. The car sat for about a year, and the more I look at it, I think some moisture or some other foreign object/substance fucked the amp up. It's just bad luck

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by csuho &raquo;</TD></TR><TR><TD CLASS="quote">yup if the magic smoke appeared its gone to amp land most likely. i wouldn't ground to the body if all possible. find a seat belt bolt or something else thats at a strong point. if all else fails run a ground to the battery.</TD></TR></TABLE>

wtf? lol. never run you ground to the battery. Wanna know why. Because you run the biggest chance of introducing noice into your system. Your ground should be short as possiable. As long as the body is clean to bare metal and is part of the main body you should not have any problems.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by csuho &raquo;</TD></TR><TR><TD CLASS="quote"> i wouldn't ground to the body if all possible. find a seat belt bolt or something else thats at a strong point. if all else fails run a ground to the battery.</TD></TR></TABLE>

This is sig worthy, lol, hey player if you are grounding to the seat bolt it still the car body, lol.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by wrx-killer-Sti eater &raquo;</TD></TR><TR><TD CLASS="quote">
wtf? lol. never run you ground to the battery. Wanna know why. Because you run the biggest chance of introducing noice into your system. Your ground should be short as possiable.</TD></TR></TABLE>
Please explain why? Not just "this is what everyone says so thats why its done".

Specifically how does grounding to the battery cause noise?
And why should the ground be as short as possible?

Please remember current starts and ends in the same place.

If you know what you are saying you are making an assumtion that is flawed.

My Boat has no chassis ground, its made out of fiberglass. Guess where the connections get grounded? And there is no noise.

 

So is it not true that your ground should be as short as possible? Should you or should you not ground from the negative of the battery? Why or why isn't it bad? I never could find out the real reason.

 

the negative terminal of the battery is connected to the chassis, so whatever else you connect to your chassis is essentially tied to ground, the reason for a short ground wire is b/c less resistance means a more direct connection to ground, think of trying to ground your amp through a 0 guage wire or an entire chassis, the chassis will obviously get the better connection...and yes to answer the OPs question, the JL amp is probably fried unfortunately, JL doesnt have any internal fuses, so you will have ot take it to be repaired unless you are VERY familiar with JL products and know what your doing

 

I have a jet boat too, 86 eliminator bubble deck sprint 19 ft. And my system is done the same way. Its the only way. The reason I say this is first is because the quicker the amp can pull ground the better the reponce is going to be. So is the bass and sound q. Now if you run your ground too your battery it has to go all the way to the battery to complete the circuit. Now in my boat there is no way I could ever here my stereo. There is a big block 482 blown chevy in the back with a b&m mini blower with basset pipes. With the motor off your not going to hear any whine but I never find out. When I ground someone system I like to see a ground point of 1/2 ohm or less. And this can happen with the way of the big 3. Any thing more then 1 ohm would be best to go to the battery some say diffrent. I do not suggest grounding to seat beat bolts because of one reason. The nut that you are offten bolting into is most likely tacked welded on and will not provide good ground. It will be enough to turn on your amp but will make it work harder because of restiance. I doid a 06 chevy truck and went to check the ground point and it was 7 ohm. Did the big three and it was 4. I had to go to the battery because there was no other choice. I'll post pics of my family boat later, So people can see it and not call me "mr me 2" I and my family work hard for our toys and playtime togther. quads, jet ski's, my cars. my parents put into me "work hard play harder". I live by it.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by shyboy817 &raquo;</TD></TR><TR><TD CLASS="quote">So is it not true that your ground should be as short as possible? Should you or should you not ground from the negative of the battery? Why or why isn't it bad? I never could find out the real reason.</TD></TR></TABLE>

The chassis is essentialy a large wire. Every wire has a certain amount of resistance.

The flawed assuption is that the chassis has the same resistance through the entire chassis, therefore it's better then a wire.

When you have resistance and large current draw you can raise ground above 0 volts. If a different connections ground did not raise up by the same amount then you have a ground loop. There will be a second ground path for current to flow.

The reason you want the wire as sort as possible is to minimize resistance in the ground path. Ideally you would have all your connections as short as possible to the battery. Since this isn't practical the chassis is ok. No better then a wire though, assuming you size the wire appropriately.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by wrx-killer-Sti eater &raquo;</TD></TR><TR><TD CLASS="quote">The reason I say this is first is because the quicker the amp can pull ground the better the reponce is going to be. So is the bass and sound q. </TD></TR></TABLE>
Electricity travels at the speed of light I dont know how much "quicker" your going to get it there. Second the frequencies your dealing with is sound which is relatively slow.

 

here's a good write up on how to check your ground. I use it on every amp install.
http://www.the12volt.com/insta...&PN=1 Or on cars I haven't done before. What do you think nsx.?

 

I'm just curious how they are taking the measurement.

It needs to be done from the - battery terminal (with no battery connected) and to the location you intend to make your ground. I dont know of many test leads that are that long.

.5 ohms is way to much resistance. While I think its an ok practice, it will point out high resitance paths. I would question the accuracy of the meter below .5 ohms. So I don't know how "good" of a ground this method garantees you.

High current paths are effected the most 100A*.5ohms = 50V!!!!!!!

You need signifacantly lower the .5 ohms for a "good" ground.

even .1ohms I would consider a bad ground.
A ground in the .005 ohm range would be a "good" ground.

A little common sense goes a long way

 

first you have to measure the resitance of your test leads if you have to add extra feet to it. Then subtract it from your readings. I have a pertty good meter from snap-on. One on the best you can buy, About 350. and its real accurate. I have yet to see a perfect ground. zero ohms. And I will probery never will-on a car chassie, lol. People are using the seat bolt and it being used here and told to be used on teamintegra.net. That will deff give you .1 ohm. I measured it. People are still going to do it because it works for them. I lean in your favor of .1 ohm being a bad ground. thats why we are seing so many amps on this boards and other failing so much. Amps over heating and such.

A little common sense goes a long way

^^^ that is so true!