Headlight dimming with only a 600RMS watt amp?

[ST0NGE 10+ year member]

Hey guys, Im new here.

I have a 2000 MK4 Jetta 2.0. I have a JBL Crown Series BPX500.1 amp and two JBL GT5-12. I have 4 gauge wiring for the power and ground wires.

I have noticed headlight dimming when i have it at a little higher than normal listening volume, with the car running and driving.

I went ahead and bought 10ft of KnuKonceptz 4GA wire for my big 3, I went with 4ga because I don't have too much power drawing from my electrical system.

I just finished doing the - to the chassis and the alternator to the + on the battery and there is no difference with the headlight dimming. I wish I had a DMM to get before and after voltages but unfortunately I do not.

I know I still have to ground the engine block to the chassis, but is that going to really help a lot? I can't find the spot to ground on my car.

I just find it crazy that I'm getting headlight dimming with minimal power draw.

Stock battery and alt by the way.

Any help is appreciated!!!

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[Bettr n' Revrse 5,000+ posts]

Unless you do all of te big 3 it won't help...

 

[LosIsATool 5,000+ posts]

Gain might not be right.. Clipping will cause drops

 

[BrownVanMan 10+ year member]

Unless you do all of te big 3 it won't help...

normally true, however, on my 77 buick it already hav a 4g ground from alt to battery so i didnt do another one.

but on the jetta i would do all 3

 

[ST0NGE 10+ year member]

Unless you do all of te big 3 it won't help...

Alright I'll try to ground the engine block tomorrow. I am looking on the VW forums but not really seeing much..hmm..

Gain might not be right.. Clipping will cause drops

Well I just got the amp's gains and all the settings on the amped setup at a local audio shop as it was a self-install.

 

[JoshC 10+ year member]

my head lights have always dimmed a bit 600-1200wrms, but why the big deal? Is it dimming enough to disrupt your driving or loss of vision?

 

[Bettr n' Revrse 5,000+ posts]

You may wanna test your batt and alt...

 

[mylows10 5,000+ posts]

also that jbl crown amp is a little power hungry,so was my fosgate 500a2 back in the day.but like said earlier do the whole big 3 .and by the way the grounding of the alt to the chassis isn't part of the big 3 ,some people will even say it doesn't help to do it.but i did.

 

[ST0NGE 10+ year member]

my head lights have always dimmed a bit 600-1200wrms, but why the big deal? Is it dimming enough to disrupt your driving or loss of vision?

I mean honestly, to me it isn't a big deal, but I would think the electrical system isn't liking it, I could be wrong.

You may wanna test your batt and alt...

I could go to Autozone for something like that right?

 

---------- Post added at 05:32 PM ---------- Previous post was at 05:31 PM ----------

 

also that jbl crown amp is a little power hungry' date='so was my fosgate 500a2 back in the day.but like said earlier do the whole big 3 .and by the way the grounding of the alt to the chassis isn't part of the big 3 ,some people will even say it doesn't help to do it.but i did.[/quote']
Isn't it alt to + on battery? lol

 

[Phoenix Risen 10+ year member]

it sounds like you have a bad grounding spot for the amp.

where is the amp grounded to? and how is it attached.

 

[Tek18 10+ year member]

not to hijack, but are you suppose to ground part of the outer piece of the alt to the -?

 

[ST0NGE 10+ year member]

it sounds like you have a bad grounding spot for the amp.
where is the amp grounded to? and how is it attached.

It is grounded in the trunk, about 3 feet away from the amp. I scraped the paint to bare metal and screwed it into the frame.

 

[Bettr n' Revrse 5,000+ posts]

Ya autozone should be able to do it...

 

[Phoenix Risen 10+ year member]

ok, as long as its good and solid.

 

[wenn_du_weinst 10+ year member]

a lot of cars have very sensitive headlights. Mine don't dim at all with 1700 //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif