Tried Everything but still have severe voltage drop and dimming

[firefighter_324]

I have a 2007 Dodge Ram Quad Cab Hemi. I have the following setup:

- Pioneer P8400H stereo

- Pioneer 8500D amp 1200w x1 at 2 ohms (This is maximum power)

- Pioneer 9500 amp 400 x4 at 4 ohms.

- 1 farad capacitor

- 1 12" 4 ohm DVC sub in a custom box I have made under rear seat

- optima red top battery

- 0 ga power/ground wire

Here is what I have done to try and fix my dimming problem:

- tried without the capacitor = same results.

- upgraded the amp power and grould wire to 0 guage wire (then 4 guage to the amps from dist. blocks)

- tried a few ground locations and ground seems good under the middle seat belt bolt. (checked resistnace with voltmeter)

- NEW alternator (factory 136AMP)

- new battery (Optima) and then tried new standard battery (Duralast Gold)

- Big 3 upgrade with 0 Ga wire (also upgraded additional grounds and power wires, cleaned connections)

- Checked and re-checked wiring/grounds

It sounds great but my headlights dim way to much .. There is no way I am pulling more amps than the alternator is putting out ..Others with more watts with facotry alternators don't have this issue..

Any ideas ??

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[sobe3yourself. 10+ year member]

this shouldnt happen. all i can think is that it's something with trucks. back when i had my silverado, i had a 0 gauge run to my amp which was wired to only do about 200 watts. i had stock alt and no big 3, but you wouldnt think you'd need it and i had pretty bad dimming.

 

[frogcase2002 10+ year member]

not sure if it will work for you but i know there was a huge difference when i got a 2nd batt. when it came to dimming and voltage drop,, mite just have to go with a high output alt.

 

[firefighter_324]

I am going nuts lol It's not like I play the music really loud but it would be nice to listen to some Brad Paisley at night without looking like a 70's Disco Ball driving down the road //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

I woudl be willing to try anything to fix, I just don't know what it would be ... My next try may be a higher output alternator, but I really don't think that would fix the problem.

 

[dragon.breath 10+ year member]

do the lights dim when you are driving or only when the truck is idling? many alternators do not make full power til around 2000 engine rpm. if this only happens at low rpm thats your problem.

also, many people never think about this but the headlight itself can cause different amounts of dimming. i have seen headlights that can go from 12 volts to 15 volts and put out the same amount of light. so they do not 'show' dimming. i have also seen the reverse. lights that will dim with a .5 volt drop.

 

[firefighter_324]

It pretty much dims all the time on the "higher bass notes"

I can rev the engine to 4,000 RPM and it makes no difference in the amount of dimming. They do not dim when the engine is not running .. Meaning I can be running off battery with the headlights on and they don't dim hardly at all..

Everything dims though.. dash lights, interior lights if on, ect ..

Even during the day when my mileage is lit up (LED display I think) that will dim also .. It drops from around 14.5 down to 12.8-13v when its running ..

 

[dragon.breath 10+ year member]

You have something wrong. First thing to do is take your truck to a autoparts store like autozone and have them check the battery and alternator (autozone does it for free )

I am thinking you have a loose connection somewhere in your trucks charging system.

 

[shpatb 10+ year member]

With that amount of power you shouldn't be dropping under 13 volts. Might be a bad ground somewhere if anything else get a HO alt, if it's not that you can just sell it again on here and make most your money back.

 

[wes669 10+ year member]

Do a big three and see what happens. Check your sub wiring also.

 

[LosIsATool 5,000+ posts]

Is your gain set right? That will cause drop no matter what you do.

 

[firefighter_324]

Thanks for the replies ... I have replaced all grounds chassis, body, ect ... (did the big 3 already)

I already replaced the battery and alternator with new..

My gain is set correctly.. The setup sounds really good but as soon as the bass hits hard it dims..

I am no professional but I have followed all the gain setting suggestions I could find .. Only thing that cures the problem is turning down the gain but then I have no bass //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

I also see others with a Charger and Challenger Hemis have the same issue .. Mopar can't **** this bad can it ?

 

[LosIsATool 5,000+ posts]

Thanks for the replies ... I have replaced all grounds chassis, body, ect ... (did the big 3 already) I already replaced the battery and alternator with new..

My gain is set correctly.. The setup sounds really good but as soon as the bass hits hard it dims..

I am no professional but I have followed all the gain setting suggestions I could find .. Only thing that cures the problem is turning down the gain but then I have no bass //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

I also see others with a Charger and Challenger Hemis have the same issue .. Mopar can't **** this bad can it ?

How did you set it?

 

[firefighter_324]

Set the volume to 30 on my HU with EQ and bass boost at flat then adjusted up until distortion then back off some ..

 

[LosIsATool 5,000+ posts]

Set the volume to 30 on my HU with EQ and bass boost at flat then adjusted up until distortion then back off some ..

Use a dmm, your clipping a high volume. Its very hard to hear clipping in the sub frequancies. If its not loud enough you need to rethink your sub stage.

 

[madcad95 10+ year member]

Its a dodge ?