Question about JBL GT150 Car Subwoofer

8 Answers


Basically i got a amp and a sub the other day and fitted it in my car. everything was working, but i notcied little sparks from the wires at the back of the amp (when you moved it abotu) because it would sometimes touch each other (the red wire and the black wire) the subwoofer used to go out randomly sometimes and come back. anyway today the subwoofer stopped working altogether but theres still power in the amp because the green light comes on which means the amps ON, but still nothing comes from the sub. I checked all the wiring and it looks correct. from grouding, to remote cable... everything seems in order. anyone know whats wrong?

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  • Anonymous Jan 13, 2008

    I had a 300 watt amplifier hooked up. Power wire ran with a in-line fuse to the battery positive terminal. Ground grounded to the frame of the truck. 12 Volt remote plugged from the stereo remote wire to the amplifier 12 volt terminal. RCA plugged to the RCA jacks on both the radio and subwoofer. My problem is that the amp for some reason or another comes on with a red light, not meaning that its on, and I knew that it was saying this because I unplugged the positive power wire to see if the amp was getting a signal, and it was indeed getting a signal from the remote wire. Then I replugged the powerwire, and the same thing happened, the red light. I came to the conclusion that the amp wasnt getting power because I tried several different guages of powerwire and ground wires and the same thing kept happening, no power, I ran it with a fuse, and with out a fuse, and still no power. I have no idea what I had done wrong, and so I came to the conclusion that my amplifier was bad, or old (I bought it 4 years ago from Can anyone help me to solve this issue? I had botten another amplifier and subwoofer, but I am not quite ready to decomission my 300 and 720 watt jensen amplifiers (which by the way, the same thing happened to the 720 watt amp that happened to the 300 watt amp).

  • oilers99dan Apr 20, 2008

    back in december i had a new kenwood deck put in my 92 4runner and 2 12 inch subs were hooked up with it. back in february the subs just stopped working. all cords are hooked up and power is going to the amp i can see the lights on. amps are still working. i've tested the speakers with a 9vlt battery and they pop like they should.. why do my subs not work?

  • Ljsharpe Sep 29, 2008

    my sub began to cut out yesterday, i would touch it again n it would start up then cut out n so on..n i tried all the fuses n they are all good, i checked the wiring n its all good but i noticed that when i unscrewed the power wire on my amp it sparked n since then the sub wont work at all, theres a red light on the amp for the power, i dont know if it was once green and now is red because its all messed or if was always red. anyways, i have two other regular speakers in my trunk and they are hooked up to the top of the amp and they work perfect. the sub is connected to the bottom. is it possible to blow the bottom portion of the amp? i have owned my 95 mustang for about 4-5 months my dad bought it off a man who apparently babied the car and the system came with the car, hooked up and all that--HELP plzz

  • Anonymous Apr 22, 2009

    aahhah im not the only lozer with a amp that has his ground wire(BLK) and power wire(RED) near each other.

    my amp is working but my subs are not cuzz the red wire kinda tuched the black wire while i was making a turn. but time to throw out that old amp and get a new one cuzz i dont want to have the same problem with my new subs



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If you have real old wires from the amp to the sub try getting new wires on it. check the little wires that go to the cone itself on the sub. sometimes they can manage to get pulled out of their terminals and make sure that thier touching the terminals on the correct spot

Posted on Oct 04, 2006

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I have a amp that has the green light on so I know the amp is good. I took the speaker out the box and hooked it up to the wiring for my 6-9's so I know my speaker is not blown but when I run it to the amp it kinda ketone little bump of bass out and then nothing else.why?

Posted on Aug 09, 2013

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For most of you your red light should be green on newer amps it only turns red when the amp is not pulling enough power or is over loaded and you should always disconnect the ground wire of the battery before wiring up amp me on the other hand my amp is working fine because i tested it with other speakers however my 12 inch sony explode has no sound is not busted and terminals are not loose or broken.... solve that one?

Posted on May 17, 2012

  • kdementedpsy
    kdementedpsy May 17, 2012

    for most of you your red light should be green on newer amps it only turns red when the amp is not pulling enough power or is over loaded and you should always disconnect the ground wire of the battery before wiring up amp me on the other hand my amp is working fine because i tested it with other speakers however my 12 inch sony explode has no sound is not busted and terminals are not loose or broken.... solve that one?



Posted on Feb 03, 2008

Same thing happend to me when i wired mine. I didnt disconnect the negative battery terminal and touched a ground(metal parts of the car) with the positive cable. Blew my fuse in half. Best buy carries replacement fuses so check it out

Posted on Jan 13, 2008

When you indicate that the red and wires on the amp were touching at on time these are most likely the positive and ground leads from the battery and chassis (respectively). If that is truly the case, check the fuse on the positive lead going to the battery or that which is on the amp to see if it is blown. When this fuse is blown, it would not be uncommon for the power indicator for the amp to still come on if the radio is turned on. I think tis is more than likely the cause of your problem.

Posted on May 19, 2007

My bakooza tube amp doesn't have the green ligth that lets me know tha its working

Posted on Apr 18, 2007

I had a similar problem....what happened is that the amp send the charge of the sparks thru the speaker, so try wiggling the wires that go into the cone of the sub... it will work, but i dont think the problem can be fixed

Posted on Jan 04, 2007

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Posted on Jan 02, 2017


  • 14 Answers

SOURCE: Car sub not working

has your amp been accidently swiched to stereo instead of mono,if so,swich it back.

Posted on Feb 17, 2007


  • 71 Answers

SOURCE: wiring on back of head unit

You don't need to change the cables from the head unit on.  Just strip of the end of the wires where the old speakers are and crimp on the proper connectors to connect them.  Alternatively you can just solder the wires directly to the speakers.  I always **** splice at least 6" of wires onto the end so you have more wire to work.  The only reason you would change the wires would be because you are putting more than 200 watts per channel.  You didn't speak of an amp so no worries.
James Mac

Posted on Sep 09, 2008


Travis Humphries

  • 1990 Answers

SOURCE: my twin jbl 12'' sub in a enclosure dont seem to be giving bass

Those 12's Need to be in a Ported Inclosure to release the Air that the Bass Produces. Use a 1 Inch Key Hole Bit and make 1 Hole at the Top Corner of Each Portion of the Box. Top Left and Top Right. Please Rate My Response! Thanks!

Posted on Feb 02, 2009

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