Need help massive viltage drop!!!!!!!

[memphismonsta 10+ year member]

Okay ill start from the beggining! i was running 3 amps and 4 12's in my jeep with everything stock (90 amp alternater duralast gold battery) and could run it a full blast and would get a voltage drop from 14.3 - 11.8 at its lowest. I added 2 rockford 75 watt rms high speakers and a small 250watt rms amp and everything went to **** extremely fast. I noticed after i did it that my voltage was dropping so low my check gauge light would come on well below 9 volts. so i did the big 3 upgrade yesterday and ran the system and popped a inline fuse that has never popped before and my voltage was still falling to around 10 something volts when the speakers were hitting. so i said screw this ill take the new amp out until i can order a HO alt and put a battery in the back also. so the new amp is removed and still everytime i run my music full it blows my inline fuse after about 30 seconds now and it never did before i cant figure out why. what should i do ?? i have an extra battery should i put it in the trunk and see if it helps with the voltage drop or is something ese horribly wrong ??? any help would be awesome im getting frustrated and the big 3 made it worse so im worried about buying a HO alt and wasting the money. I'm somewhat new to large scale systems so any help would be awesome thanks in advance.

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[gckless 5,000+ posts]

List all equipment in your system. What size wire, what size fuses, what amps, subs, box, everything.

 

[memphismonsta 10+ year member]

2 250watt rms memphis power reference in memphis box with 750 watt rms old school zapco amplifier. 2 re audio 2000watt se12d4, 2 1500 watt lanzar amplifiers pushing them in a dual ported box tuned to 38hz 1.5 cuft per chamber as required by re specs. 2 rockford prime 75 watt rms door speakers that i was pushing with a 250 watt rms kenwood but i took it back out when the problems occurred and just have them hooked to the head unit. all i was trying to do was add some highs cause the bass was so loud u couldnt even hear the highs.

 

[memphismonsta 10+ year member]

my bad forgot the wire i did the big 3 with 2 gauge wire ... i have 4 gauge fused by battery going to the back of the car going to a capaciter and then 4 gauge from there to all the amps . my grounds are 2 gauge to caps and 4 gauge from there to all the amps.

thanks for the quick response and helping me i appreciate it. i learned since that caps dont help but i like the volt meter on it so i kept it in.100 amp inline fuse is what keeps blowing i cant find a higher fuse i know it should be fused with what the wire can handle but i cant find a 200 amp maxi fuse style i can and will replace this if need be but it worked fine before and i restored my system back to what it was before the problem occured

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[memphismonsta 10+ year member]

what i assumed happened was i added 1 to many amplifiers to my stock electrical so i tried to do the big 3 to see if it would help . It helped a little but i was still having a HUGE voltage drop and it popped my fuse. so i assumed if i just removed the added amplifier everything would return to how it was and i would wait until i upgraded my electrical before adding the amp for the highs. But i have removed the amp and am still popping fuses at full playing volume (32 of 55) (32 is where my head unit starts to distort) and i still have a large voltage drop. the only thing i can think of is by doing the big 3 i allowed my amps to pull the power they actually wanted and its exceeding the 100 amp fuse ?? im not really sure to be honest. i am going to run another 100amp fuse and 4 gauge wire to the back so its 200amp fused and see if that helps but im not sure if im even on the right path im getting frustrated and grabbing at straws. should i take the rockfords back out and see if that helps??

 

[audiobaun 5,000+ posts]

Id go get your voltage checked out at Orileys/Autozone ..Its FREE, they can test the battery alone, and should be able to test the alternating current as well,with ac/lights ect(a load)and without a load..You may have damaged your battery,or even your regulator inside your alternator.As for your maxium size fuse for 4ga wiring, it should be no bigger than a 150 amp..Here is a chart to the far right for Power wire size, and Fuse rating,that may help you

Recommended Power and Ground Cable Sizes & Speaker Wire Size and Length

 

[audiobaun 5,000+ posts]

What vehicle do you have?

 

[memphismonsta 10+ year member]

Jeep grand cherokee laredo 5.2l and the battery is a brand new dura last gold. and if the systyems off the alternator and voltages r perfect. at idle i have 14.3 volts. I have another new battery on my trickle charger right now if i install it in the trunk will it help?? i dont think it will since when the car is running it runs off the alternator but i will go out and buy a 150a fuse and install it any other suggestions would be awesome EXAMPLE i was cruising around my neghborhood pulled in my driveway sat for 10 seconds listening to my system slam and noticed my check gauge light was on because my voltage was well below 9 volts ... turned the head unit off and 15 sseconds later was back 2 14.3 volts

 

[audiobaun 5,000+ posts]

Your alt can keep up with the Draw..you will eventually ruin your batt, or alt, or both if you continue..Extra batt may help..worth a shot..be best if you had two agm batts to work with.

 

[memphismonsta 10+ year member]

ok kinda what i thought figured the extra amp sent it over the edge. I have not been running it... after i blew the fuse i didnt run it til i removed the new amp and then i tried again and it blew the fuse again so i havent run it since. Ill go buy a High output alternater and add a second battery . The alternator is old so ill replace that first. im worried that iff i put the extra battery in now it will make my alternator work even harder than it is already it cant keep up with the current draw of the system let alone charge 2 batterys i dunno ill give it a shot ill let u know how it goes i guess.

 

[Sleeklsc 5,000+ posts]

Do you seriously have a single run of 4awg for all that crap?

Get 0awg ofc and run it to the rear- Use for power and grounds, get rid of the cap, get the proper sized fuses. Thats all i'll comment on for now, I'm starting to get a headache.

 

[memphismonsta 10+ year member]

ya i started small and kinda got big im going to run another 4 awg wire back and run 2 amps from 1 and 2 amps from the other. which will also help my fuse blowing issue. like i said this is my first big system ive been into car audio for 12 years now but never more then 2 subs 2 amps this is my first semi big build. but before i fucked everything up adding the 4th amp i had that system so loud it was to painful to drive almost impossible i have all the amps on less than 25% there output. this is a learning exsperience for me why what wire should i be running back ??? my grounds are 2 gauge

I was happy with my setup and i had way more bass than i could handle all i was doing was trying to amp up my highs so i could actually hear a little bit of the lyrics when everything went haywire on me. I'm upgradinbg the alternator adding an extra battery and another 4awg 150amp fused power wire. i just dont understand why after i removed the new amp im still drawing more amps than i was before adding it. only thing i can think of when i did the big 3 i allowed the amps to pull what they wanted not what the wires allowed and now im pulling over 100 amps at full volume)

 

[memphismonsta 10+ year member]

You really think my wire size is causing the voltage drop ??? Cause if so tell me before i buy a new alternator. ill upgrade everything to 0 gauge and see what happens

 

[Sleeklsc 5,000+ posts]

What's the model # on the 2 lanzar amps that power the re's?

 

[memphismonsta 10+ year member]

vct1500d