new amp and new batt and everything goes crazy...please help me

[allout13 10+ year member]

I hooked everything up as shown in the picture...

at first the amp would show that it was getting power but no power was coming out of the speaker outputs. I gave up and turned of the power and removed the keys from the ignition and all of the sudden the amp as well as my hu power back on and the amp is now giving output to the sub. The amp is not putting out near the power it should though and I cannot get anything to shut off. When the car is off the rear batt stays at 12.4volts and does not change when the car is running. With the amp on and the car off, my dmm shows no change in voltage when the bass drops. what the fuck is wrong?

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[ThatChevyGuy 5,000+ posts]

Weird...

 

[kovemaster559 5,000+ posts]

looks good to me !

 

[Beerdrnkr 5,000+ posts]

Strange. I have my setup exactly like yours. //content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif

 

[shizzzon 10+ year member]

there should be another fuse right before the power line reaches the back battery and there should also be a solenoid before it reaches the battery as well.

Though that isn't what is causing your problem.

So you say the amp ONLY comes on now when you shut the car off?

When you say the HU comes on when you turn the car off, sounds like it's hard wired to the battery, correct?

Disconnect the remote wire going to the amp first until you fix the head unit problem.

I am not for sure as to what can kick the head unit back on in an off position so it sounds as if something is definitely wired wrong. There should be no 12v turn on signal active when the vehicle is off.

Go over your entire wiring to the stereo.

 

[DidUHearThat? 10+ year member]

I think you may have more than one problem going. You may have a loose/intermittent power connection at the amp or fuse holders (very common problem). Retighten all your power and ground connections

Also check your remote power leads to the headunit, and the headunits power and ground connections.

If your rear battery voltage does not increase when the car is running then it may not be chargeing. Check it's fuses and power connections to the main battery. Is there a battery isolator inline? If not, then it has to be a loose power/ground connection or missing/blown fuse.

 

[allout13 10+ year member]

the amp showed power when the car was on and off but it only gave out put when the car was turned off for the first time but now it gives output regardless. the headunit never turned on when the car is off before but now I cant get it to turn off. also I cant turn on the car unless the back battery is hooked up, when I disconnect the rear battery there is no current in the car.

what do you mean hard wired to the battery?

 

[allout13 10+ year member]

I think you may have more than one problem going. You may have a loose/intermittent power connection at the amp or fuse holders (very common problem). Retighten all your power and ground connections
Also check your remote power leads to the headunit, and the headunits power and ground connections.

If your rear battery voltage does not increase when the car is running then it may not be chargeing. Check it's fuses and power connections to the main battery. Is there a battery isolator inline? If not, then it has to be a loose power/ground connection or missing/blown fuse.

I have no battery isolators. I will check the fuses and grounds then...

 

[DidUHearThat? 10+ year member]

there should be another fuse right before the power line reaches the back battery and there should also be a solenoid before it reaches the battery as well.
Though that isn't what is causing your problem.

Agree, x2.

This isn't your current problem, but I also think there should be another fuse near the second battery. Not everyone recommends this, but I do. If your power cable shorted out in the middle (like at the fire wall) the fuse near the main battery would pop and protect the wire inbetween the main battery and the fault to ground, but there would be nothing to protect the wire from the second battery to the fault to ground. That section of wire would get red hot, melt it's insulation and ground out the battery till it explodes and/or sets your car on fire.

 

[DidUHearThat? 10+ year member]

the amp showed power when the car was on and off but it only gave out put when the car was turned off for the first time but now it gives output regardless. the headunit never turned on when the car is off before but now I cant get it to turn off. also I cant turn on the car unless the back battery is hooked up, when I disconnect the rear battery there is no current in the car.
what do you mean hard wired to the battery?

Hmm, maybe you need to take a step back and get your car working properly first.

Disconnect the fuse to the second battery and amplifer. Ignore the radio for now.

Your main battery should still be connected to your alternator right? It should start normally and power everything in your car normally. Maybe you accidently disconnected the main battery power or ground.

 

[DidUHearThat? 10+ year member]

Be very carefull. Your working with a lot of amps here, and power that can flow from three different sources, 2 batteries and the alternator. Do not let the batteries or any power cables short to ground. Carefull to not let any tools short the terminals on the batteries or positive to ground.

 

[allout13 10+ year member]

Hmm, maybe you need to take a step back and get your car working properly first.
Disconnect the fuse to the second battery and amplifer. Ignore the radio for now.

Your main battery should still be connected to your alternator right? It should start normally and power everything in your car normally. Maybe you accidently disconnected the main battery power or ground.

I will try and disconnect it and see if the car starts without it.

none of the fuses are blown. the car only has electricity when the rear batt is grounded, but when the ground from the rear batt to the chassis is disconnected there is no current in the car, but the amp still shows that it has power

 

[allout13 10+ year member]

Be very carefull. Your working with a lot of amps here, and power that can flow from three different sources, 2 batteries and the alternator. Do not let the batteries or any power cables short to ground.

what do you mean?

 

[DidUHearThat? 10+ year member]

I will try and disconnect it and see if the car starts without it.
none of the fuses are blown. the car only has electricity when the rear batt is grounded, but when the ground from the rear batt to the chassis is disconnected there is no current in the car, but the amp still shows that it has power

Okay, you need to fix this problem first before you can move on to the stereo. Disconnect the negative power lead to the rear battery. Check your main battery connections and ground. Your car must work normally without the rear battery.

 

[teen 10+ year member]

sounds like a bad ground to me. my sub/ amp used to go crazy, turns out it was a bad ground.