subbs turning off ! cutting out.

[mitchy_vn]

Hi all, i got 2 clarion PA15's in my car, running off a kenwood mono block amp.
Problem is when im driving, or car on idle the subs turn off. The map is stil on tho. So what i have to do to get them back on it turn off car and turn on again.

IM runing 8G writing from bat to amp, and using standard bat for car.
I know i need minium 4g buh i think the problem is the stantard batt.

will it be a good idea and cheaper idea to buy a second normal batt and place it in the boot and connect it parallel, instead of buying a heavey duty batt. (as u can see i think the problem is im not getting enough power, as wen the system is on full the lights go f0orm normal to dim normal to dim)
also if anybody knows the price of those heavey duty bat. thanks

(also this morning my car wudnt start, batt was flat as, but i lefted nuffin on,, last night system was on whole night n turned off 4 times, i think i really drained the bat.

 

[thekid93]

are your subs wired in right? i just had a problem with mine cutting off, added a another type r and wired it wrong for a bit, would pplay but when it hit 20, they both cut off and needed a restart of the car.

fixed the wireing and now they go nuts

 

[mitchy_vn]

they r wried up correctly, im pretty sure but jst the main power n ground cable are to thin.. is only problem wit wiring

 

[acarmody]

First upgrade the wiring, then make sure the gain is set properly, and also check that the ground cable has a really good connection to the chassis.

 

[mitchy_vn]

oh ok yeh il upgrade wire n check ground, the gain is set right.

 

[Luke0011]

This sounds more like a problem with the amps going into protection because of either heat, over current, or short circuit. You say the amp stays on. Obviously a light on the amp is telling you this. What colour is the light and also is there another light on the amp somewhere. A lot of amplifiers have a green light telling you its on and also have a red light that comes on when the amp goes into protection mode. It could be a single light that changes color or 2 seperate lights. You need to tell me if the light changes colour or turns off and the red protection light comes on.

It is definitely not a good idea and cheaper to upgrade to a heavy duty battery than add a second battery.

The subs power draw lets say from a 13.8 volt supply would draw 86.9 amps of current so in theory the 8 ga power wire will start to burn. It technically can supply up to 75 amps of current. But this current measurement is dividing 1200 watts peak music power of both the subs by the voltage. The subs power rating is the amount of power it can handle before the voice coil starts to burn so it wont be drawing that many amps of current. Even measuring the RMS power ( root means square ) which is the effective or working power the sub generates at a 12 volt supply is 70.6 amps. Even at 11.5 volts which is generally the point at which an amp shuts down is 73.7 amps which your 8 gauge power wire can still supply.

This is assuming the amplifier can supply the amount of power required. Having said that upgrading to 4gauge is strongly recommended. It can supply up to 150 amps of current from a 5 metre length.

Its unlikely that the voltage drop caused by the battery being worn or alternator wearing out or voltage drop of the small power wire causing the amp to shut down and having to turn the unit off and back on again for the subs to output again. But it may be the case so easiest and cheapest way to solve the problem is replace the fuse at the battery with an 80 amp rating even if it does already have one. Fuses wear out. If problem persist then upgrade to 4 gauge power and earth. Make sure it is a solid connection to bare metal from the amps earth terminal to where you connect it to the body of the vehicle. If problem persists, load test the battery at an auto electrician's workshop. They may quickly do it for free if you ask nicely. They will probably tell you the battery is worn or under charged. They may tell you to put a battery charger on it for 12-24 hours or replace it. You dont need to upgrade to a heavy duty battery. An optima yellow top would cost around 300 but this may not be the cause of your problem. Just buy a normal battery for around 80 dollars. If problem persists I would then take it to a specialised car audio shop. They have other amps and subs to use with your system to find out if the problem is in the product or wiring.

Its impossible to tell why the problem is occuring but a process of elimination is needed. The first parts you can do your self and then get it professionally tested.

 

[mitchy_vn]

thanks mate, yeh first thing il do is change my fuse, upgrade the wiring. and let you know how i go.
(il check to see what happens with the light's on the amp, and see if they change colour)
until then i wont play it high or not much at all, dont wanna risk any damage.

 

[aazn]

i dont think the problem lies in the power cable..

i think its the earth.. btw which amp you running... im pretty sure it will not be drawing more then 50 amps. (~500wRMS)

it may say MAX 800watts on it.. but then your looking at RMS

either way.. check to make sure the earth is done properly..
i find putting a self tapper though the cable itself and into the chassis is a really good earth (keep the original terminal there)

if you want to upgrade your wiring, go down to jaycar/jb/autobarn and just buy the 4GA by the metre.

 

[mitchy_vn]

To Luke0011 about the lighting on the amp, By the way all i have a kenwood 1800watt mono block, um it has to lights on it a blue light to says it on, and a red light when music playing.
when the subs cut out again i took a look at the amp and blue light stil on but red light was off.
yeh its getting bad now everytime i turn it up for abit it'll cut out. so i dunt play it anymore, imma check ground on weekend n probly buy myself 4g .
it feels lik the system it drawing more power then what the alternater can make lol since its cutting out while driving.

 

[acarmody]

The alternator is putting out about 80amps (I think for your model) which at 14v means about 1120 watts of power. And your system wouldn't use close to that continuously. And then the battery can supply hundreds of amps (think starter motor) on demand. So your electrical system (assuming all in good working order) can easily keep up.

I would check those cables first.