amp not powered? need help plz
Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=9329
Printed Date: August 18, 2025 at 3:35 AM
Topic: amp not powered? need help plz
Posted By: mikerotch5
Subject: amp not powered? need help plz
Date Posted: February 10, 2003 at 3:18 PM
hi, my name is mike and this is my first post anyway down to business... i just bought a new 12" Alpine Type-R and a box, I hooked it up to my amp and the amp does not turn on, i used a voltmeter and there was no power going to the amp, i checked and it turned out the inline fuse had blown. I replaced it and it still doesn't work, i checked the ground power and remote wires, and they all seem good. so i got a new amp and hooked it up and surprise, it still doesnt work, i have no clue why not and am starting to get frustrated, knowing me ill eventually punch a hole in the sub with a screwdriver, any suggestions are welcome
Replies:
Posted By: Derrik
Date Posted: February 10, 2003 at 3:38 PM
1. CALM DOWN. 2. You said you got power from the main line? what about the remote line? any voltage on that? 3 if step 2 doesnt solve it then start reinstall again. Dont get frustrated. self-install is fun. If things don't work right now...go get some rest..come back out later and you'll be supprise =) Let us know...
Posted By: BmpnSilvi98
Date Posted: February 10, 2003 at 3:40 PM
Is there power going to the amp after u replaced the fuse? U need to check the remote wire with a volt meter to see if it has juice also. Check all the connections the pre-amps in the bac of ur receiver and on ur amp also make sure the remote is hooked up and has juice. and make sure u have a good ground not paint and to the floor pan somewhere
-------------
Justin
Hey man what do u have in ur trunk? "mtx." Well they sound like legacy's to me
Posted By: mikerotch5
Date Posted: February 10, 2003 at 6:05 PM
well i failed to mention that i did check the remote and it did have power going to it, i checked the back of the receiver and it looked good too me, i'm pretty sure the ground is good, because i used the same ground when my old amp used to work. yes it is getting power now that i changed the fuse.
Posted By: wvsquirrel
Date Posted: February 10, 2003 at 10:15 PM
Never rely on things "working" from previous installations. Double check your grounds (bare metal and grounded to the chassie/frame). Make sure your power and ground wires match in size (4 gauge power gets a 4 gauge ground, 8 gauge power gets an 8 gauge ground, etc...) If you blowing the inline power wire fuse, check the entire wire for gashes/bare wire. You could be shorting out under the dash or at the firewall, thus causing the fuse to blow. Trace the entire wire to be safe. If you want to check the amp, run a seperate power wire outside the car to the amp. Basically running the entire system outside the car (power, ground, speakers, remote line, HU connections, etc. Keep it exposed until you know its working. I've done this many times, and it helps avoiding tearing the entire car apart for no reason. All you need is a little extra wire and patientce ------------- Squirrel
"No more Cpt. Kirk chit chat"
If its too loud, then you're too old
Donate to the12volt.com
Posted By: mikerotch5
Date Posted: February 11, 2003 at 1:45 PM
well i tried powering the amp with another power source and it still doesnt work, that means its the remote that is bad, but there is power going through it, maybe its not putting enough power out? when i have time and wire ill try to run the remote outside the car.
Posted By: sparkyssb
Date Posted: February 11, 2003 at 8:46 PM
How many volts/amps is the remote providing to the amp? Many times, when the remote does not provide enough to turn on your device(s), you can use a relay. You hook the remote wire to the grounded relay. Then, you provide a constant positive (such as from your positive feeding into the amp already) and have that switched by the relay. The switched wire is your new 'remote'. Boom, enough power to turn on the amp. Hope this helps!
Eric (187)
Posted By: mikerotch5
Date Posted: February 12, 2003 at 1:00 PM
i checked and the remote is putting out 2 volts
Posted By: par3721
Date Posted: February 14, 2003 at 5:00 AM
should be 12 volts. maybe cold solder joint or bad crimp (always solder). try the relay.
Posted By: esmith69
Date Posted: February 15, 2003 at 9:19 PM
Check the remote wire for 12 volts at the back of the head unit. If you get 12 volts there but only 2 volts at the other end of the remote wire, you know something is wrong with the wire itself. But before you go and run a new wire in the vehicle, do what wvsquirrel said and run a temporary one outside the car first, just to verify that this new line will turn on the amp.
Posted By: mikerotch5
Date Posted: February 16, 2003 at 8:16 AM
Well i checked the wire coming out of the reciever and only 2 volts are coming out, I hooked up the wire to another power source in my car and the amp turned on, but no sound, so i suspect the head unit is bad, its the only thing i can think of.
Posted By: esmith69
Date Posted: February 19, 2003 at 9:20 PM
I had this exact same kind of thing happen with a customer's car a couple weeks ago. Their head unit was not under warranty anymore and my solution was to tap in to the +12v accessory wire in the radio's harness. I don't think anyone leaves their car with the key in the accessory position without the radio turned on, so I doubt you'll have to worry about killing the battery  . It's a quick and simple solution--just something to consider. Keep in mind that this is the same wire that tells the head unit to turn on. As a general precation, I recommend you don't connect more than one external amplifier turn-on using this method. Good luck!
|