Power issues

[Codymac88]

I'm running two Death Penalty 18s, wired at 1ohm to a Memphis Mojo 4000.1. I'm running 3 Optima Yellowtops, all 1/O cable and a 300 amp alt but for some reason it still drains my volt meter down hard when it hits the lows...any idea what I could do to solve this issue, besides batteries out the ass and multiple alts? I've tested all of my batteries with my volt meter, they are pushing 13.70 with the truck running so they ain't dead, I don't know why it's draining so fast. It shoots right back up to 14 volts after I turn the bass down but I want that shit to be solid!

[Gregorio253]

Yellow tops are great battery's but have you looked at xs power any they will be a little more expensive but you get a warranty as you do yellow tops I know that you wouldn't want to just but different batteries but if you have that kind of money xs power would be well worth looking In too I have a d3100 doing great with a dd m1c only about at 1800 rms but the battery is great and I would recommend a bigger xs because there great audio battery's

[ChevyBoy95]

Could be a few things...........

1. That alt isnt giving you 300a

2. Those Optimas might have some dead cells [test them separately]

3. You have a choke point in the charging system [not enough wire to transmit current]

4. You volt meter is inaccurate [Check it with a reliable DMM during a full load]

My first test would be #2 (disconnect the batteries and test them individually)

Then I check to see if the volt meter is accurate

Then I would get the alt load tested.

[ChevyBoy95]

I'm running two Death Penalty 18s, wired at 1ohm to a Memphis Mojo 4000.1. I'm running 3 Optima Yellowtops, all 1/O cable and a 300 amp alt but for some reason it still drains my volt meter down hard when it hits the lows...any idea what I could do to solve this issue, besides batteries out the ass and multiple alts? I've tested all of my batteries with my volt meter, they are pushing 13.70 with the truck running so they ain't dead, I don't know why it's draining so fast. It shoots right back up to 14 volts after I turn the bass down but I want that shit to be solid!

no, that means the alt is charging at 13.7v

they aint pushing nothing......

Go through the checks i posted above.

[Gregorio253]

You would have to find maybe a car audio shop that can test your alt because autozone and places like that can't really test your alt properly

[rockFord_Expedition]

With your vehicle running, and system off what is your voltage at the alternator charging post?

It sounds like you aren't getting 300A out of your alt. Are you raising engine rpm's when going full tilt?

[Gregorio253]

And you need to test batteries with truck off and should probably let them get to resting voltage takes about 24 hours or overnight

[Rich Schenk]

What does that alt do at idle and who makes it?

Are you running a yellow top under hood or just the 3 in the back?

How many runs of 1/0 do you have to the back?

What are you grounded too and how many grounds?

Have you done the big 3 or big 4?

[Codymac88]

Thanks guys, I'll test them all individually tomorrow. It does it when I'm at an idle, it helps to rev the engine, but it still drops voltage. I'll get the alt tested too just to be safe. The alt is putting out 13.70 with the system off and truck running, I feel like a dumb ass that I didn't realize that was why the batteries were reading that, cause the truck was running. Haha but thanks guys, I'll update when I test everything tomorrow

[Codymac88]

Just the 3 yellow tops in the back, one run of 1/0 run to the back and batteries in series with three frame grounds. Also have 1/O from the alt to the distribution block under the hood