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Topic: power question (head unit and amp ) (Read 1846 times) previous topic - next topic

power question (head unit and amp )

ok i hooked up my head unit to the battery (with a fuse)  and the batt. remote, acc. all to the same power wire. so the key doesnt have to be on to have the radio play.  but now my amp light is on allthe time . is that gonna burn ot out.  and i would prefer it to go off,. so if i wanted to how could i kill the power to it from like a switch if i know im gonna be away from the car awhile.  that and with me hooking up the HU to the batt. is that gonna kill it faster. or just when the car is off.  will the alt keep it charged while running. or is it just a draw on the batery
trick flow street heat intake , 24lbs injetors, ported GT-40's (Chip) long tube headers. and a Performance Automatic C4, with a hurst shifter!

Re: power question (head unit and amp )

Reply #1
Well, I have no idea what radio or amp you're running, but there's usually a "trigger" wire from the radio to the amp telling it to turn off when the radio is off. Everything hooked to the battery = no "off" signal.
Death awaits you all with nasty, big, pointy teeth.

1988 5.0 Bird, mostly stock, partly not, now gone to T-Bird heaven.
1990 Volvo 740GL. 114 tire-shredding horsies, baby!

Re: power question (head unit and amp )

Reply #2
The REM wire (should be blue). Put a switch in the dash for that wire and you'll be able to turn the amp off. Even better, connect it to the back of the head unit instead of directly to the battery. That way, when you shut the stereo off the amp should shut off too.
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

Re: power question (head unit and amp )

Reply #3
I believe on most headunits the ignition switch wire is red. If you hooked up the red and yellow wires together it will never turn off, and when the cd player is on, the amp will be on as well. If you put a toggle switch on the red wire then you can turn on and off the cd player whenever you want and the amp will turn on and off as well.

edit: i missed that you hooked up the remote antenna to the power wire as well. On the back of the headunit there will be a wire to connect that to. I will be a solid blue wire and more than likely say antenna, or remote antenna. Hook the amp signal wire to this wire and it will turn on and off with the headunit. The only wire that should be directly connected to the battery is the yellow wire on the back of the headunit

Re: power question (head unit and amp )

Reply #4
i have a pioneer 5500 cd player head unit. and a 4 channle 300 watt piooneer amp. i only hooked the power to the headunit directly to the batt. bc the cars wires were hacked and coulnt get them rite . so i gave up and ran it that way. besides i like not having to have the key on  to have the radio play.  yes i have the Rem wire hooked up off the headunit. but thats to the batt/memory wire off the H.U.  and thats hooked up to the power so i guess it just stays on. .

good idea on the switch. but what if instead of off the remote wire i hooked it to the power wire to the amp. .

as a refresh i will put it down like this . batt. 2 power wires one to the amp. the other to the HU  batt/memory and remote hooked up to the HU power wire = the amp light on all the time. with the power of the HU off and the face plate off.  just do the switch?
trick flow street heat intake , 24lbs injetors, ported GT-40's (Chip) long tube headers. and a Performance Automatic C4, with a hurst shifter!

Re: power question (head unit and amp )

Reply #5
Quote from: CougarCoupe88

good idea on the switch. but what if instead of off the remote wire i hooked it to the power wire to the amp. .

That's a bad idea for two reasons:
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  • The switch would be carrying more current than it has to, meaning you'd need a heavy duty switch, and
  • Every time you turned the amp on and off you would get a loud "pop" sound as the amp gets a power surge. This sound could damage speakers and subwoofers.
The blue wire is the one you want to switch. If you were smart you'd put the stereo "acc" wire on the same switch. That way you could shut the head unit completely off when you wanted, such as when parking the car for a few days, but you'd still be able to use it without having the key on.
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

Re: power question (head unit and amp )

Reply #6
i get what you mean. see im not 100% sure on what i can and can't get away with so i did what i knew i would get away with . i have to go behind the radio anyway so i'll  run some wires to a switch and call it a day. 

thanks everyone .
trick flow street heat intake , 24lbs injetors, ported GT-40's (Chip) long tube headers. and a Performance Automatic C4, with a hurst shifter!