Lights flicker and dash goes crazy when bass hits

[Mark R]

My little bro has a Seat Leon (for most practical purposes it can be regarded as a VW Golf).

We've added a 12" sub powered from a 260 W amp, and changed the stock head unit for a reasonable Alpine MP3 playing one.

The prob is that whenever you get a big bass hit, the headlights flicker and the dash goes crazy - half the display goes out and starts flashing randomly with all sorts of random displays. Similar things happen to the power window control illumination, etc.

A friend has told him the solution is to add a couple of capacitors. But I'm not so sure.

Stock battery & alt. Batt voltage is 14.0V under no load, engine running.

Please advise.

 

[Saga]

A capacitor may resolve power fluxuation, but in this case it actually sounds like it's alternator drain. I'm by no means an expert, however - but I did throw in a 12 farat capacitor in my truck when the 2000w mono made my lights dim visibly inside and out and my issues have been resolved since. In my experience, a capacitor is a cheaper solution than upgrading the alternator and may quite frequently resolve minor power issues.

Though, I also recall hearing quite a bit of bitching from people about VW's in general with electrical issues so you might want to google.

 

[steveox]

Sounds like your alternator can't handle the juice. Check out the12volt.com they have good information on the topic. Many people are against capacitors but it is a possible solution to your problems. That or a 2nd battery.

 

[radioouman]

I used a 1 farad capacitor to help my JVC stereo in my Saturn. The Saturn's wiring wasn't heavy enough, so I had a bigger wire connecting the power lead of the radio to the capacitor. When I turned on the car, the capacitor would charge and provide additional instanteanous current when required, then would charge up again. It allowed me to turn the radio up higher without distortion and the lights in the radio wouldn't dim when the bass would punch. I'm sure that you could do the same thing with a capacitor in line with the power leads close to the amplifier.

In my Saturn, teh capacitor could power the radio for about 15 seconds after turning off the car. Also be careful to insulate the terminals on the capacitor since a charged cap can deliver a huge current for a short period of time if shorted.

 

[jtvang125]

How's the amp wired? Is it wired to some wires inside the dash or is it connected to the battery?

 

[bruceb]

The high powered amp should go directly to the Battery thru a fused wire.
Run it thru a high power relay. Wire it so that when you turn on the Radio
it will energize the relay coil. Relay contacts in series with the battery feed
to the amp. Most radios, have a Amp Control lead for this purpose.

 

[Mark R]

The amp is connected via 4 AWG wire direct to the battery. I've taken a second feed as well for another amp, but that amp isn't installed yet. I'm waiting to solve these probs first.

There are no relays, instead the remote output from the head unit is used to control the remote input to the amp.

I'm not sure it's the additional wiring that's the problem, as it causes general electrical problems in the car - dash goes crazy and starts displaing random stuff, the headlights (HID) go out and flicker, etc.

So, that's why I'm wondering about earth bonding, etc.

 

[The Stigenator]

Usually when the display resets and stuff, there was a 'gap' in the electrical circuit.. meaning your amp took up all teh charge and the computer reset.

THis is not good.. put in a 2nd battery or use a cap.

 

[bruceb]

Check out this link:

http://www.electronixwarehouse...lifiers/installamp.htm

A decent value cap will be costly .. you may find it at other sites for less
but this site at least takes you thru the problems and how to solve them.

That amp is going to pull at least 21 Amps at full blast
How good is the ground ? ? ? Also a 4AWG to the chassis near the battery.
Personally, I would upgrade the Alternator to a heavy duty unit.

Check this site:

http://www2.partstrain.com/v5/...N+GOLF+2006+Alternator

Odds are your car has the 90Amp unit .... I would replace it with the 120Amp unit ... problem would
be gone. Also depending on how old the battery is, I would replace it with the largest rated unit
that would fit in the available space.

 

[spidey07]

Make sure you have a good clean ground.

Or possible you're just playing it way too loud. If it sounds anywhere near distorted, it's too loud.

 

[LTC8K6]

Hold the engine at about 2K rpm and see if you still get the weird behavior.