Question about Jl Audio 300/4 Car Audio Amplifier

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Wrong connection continuation

FIRST QUESTION: I bought a stinger 1 farad capacitor, unfortunately i installed it wrong. The positive of the capacitor to the ground and the negative of capacitor to the B+ of the baterry. My 300/4 JL amp don't work also with my sufwoofer amp. What should I do. I may have damaged the capacitor for my subwoofer amp as well.
REPLY: You should have blown a fuse. Check the main power fuse feeding the system (usually at the battery). If it appears to be good, you'll need a multimeter to check the voltage at the B+ and remote terminals of the amplifiers. Place the black meter lead on the ground terminal of the amp when testing. .
SECOND QUESTION: When I turned ON my system my amps stays off (doesn't power on). Meter reading from ground to remote is 24.5v while terminal to ground is 2.4v. When its OFF, my terminal reads 24.5v and remote 0v. What should i do to fix the problem?

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  • JingJing Dec 17, 2007

    There are 2 split fuses from the terminal. They are not blown but what i did is i cleaned the fuses terminals and replace one, installed them back and everything works fine. Thank you for suggesting of checking the terminal.



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If you're installing this in a vehicle with a 12 volt charging system (most automobiles are 12v), I think the batteries may be dead in your multimeter. You shouldn't read anything over ~15v.

When you measure this again, place the black lead on the ground terminal of the amp.

Posted on Dec 17, 2007


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You should have blown a fuse. Check the main power fuse feeding the system (usually at the battery). If it appears to be good, you'll need a multimeter to check the voltage at the B+ and remote terminals of the amplifiers. Place the black meter lead on the ground terminal of the amp when testing. .

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