FTO AUSTRALIA

Hey guys I'm curious to know how earthing works.

Firstly does earthing involve the whole car?

Or does it just involve just individual electrical items?

My trouble is that whining noise my head unit makes during acceleration. It wasn't that big a deal until my alternator regulator all of a sudden decided to quit on me. I didn't think it had anything to do with my head unit but after I got the alternator rebuilt a few months ago, it looks like that the same problem might be occurring again.

As we've covered numerous times in a lot of threads, the voltage meter seems to be erratic at times and I've got a strong feeling it's related to my amp and head unit.

Any thoughts?

I now wanna properly earth my amp and head unit if they already aren't so any help on how I can do this?

Your headunit should be earthed adequately through the factory ground wire coming off the wiring loom to the headunit.

As for your amplifier, make the following is done:
- ground wire is less than 30cm and attached to a BARE METAL (not painted) surface
- ground wires are at least as large in diameter as the largest power wires
- RCA and speaker cables are not run together with power wires

It usually helps to upgrade the negative ground from your battery too.

Earthing kits are generally only effective if the current ones are inadequate. You'd be better off just buying power wire and running new earths yourself (eg battery negative, alternator ground, engine block, etc)

Sweet answer!

Informative and straight to the point! Bravo!

I will see what I can do with that. Hopefully my alternator regulator isn't shot to hell 2nd time around.

Have you try a audio filter (aka engine noise filter)? What type of head unit u running anyway?

A Pioneer one.....coz at work can't remember what model. I'm guessing the amp is causing the problem as supposed to the head unit. It's really just started messing with my alternator again I think!

Did u hook them up yourself of someone else did?

Do u know if the cable are running seprately like left on one side & right on the other side of the car, because u can get the buzzing noise problem if you run left & right channel cable together.

Noise filter may not work, you need to work out where in the system noise is coming from before you can isolate it. Here's some tips:

- ensure that the amp is only grounded at one place (the negative terminal). If the amp is screwed directly into the chassis it can create a ground loop, which is bad mmkay?

- check your RCA cables to see if they're damaged, or try a different pair

//edit: By the way Kev, what you're referring to is when the power and speaker wires are run together, not the left and right speaker wires.

Sorry guys electrical wasn't my strong point in physics. It was installed at the Hi-Fi supermarket if that helps.

Either way, I have to rectify this problem coz my alternator has only ever started playing up when I got the amp. Especially after I've already rebuilt the bloody thing!

Then shouldn't you be going back to HiFi supermarket??

kid_dynamite wrote:
//edit: By the way Kev, what you're referring to is when the power and speaker wires are run together, not the left and right speaker wires.

Thanks bro

Good point Ben............or should I try to earth everything first?

What would you do?

It was months ago when I got it installed........

How long was months ago?

I dunno, only reason I'd go back is cause im not so good with electrics...

I'd probably say around August when it got installed. I had the alternator rebuilt around October. Now the voltage needle is watching the tennis again and it's funny how it only does it when the head unit/amp is switched on with other things like indicator, heater etc.

Maybe I should learn about electrics one day......

Nacho...I will look at it for ya...should be able to suss it out in 30min or so...tell me when and where and I'II drop in after work.

I wanted to install and earthing kit...can you get them somewhere or will i juts make it up myself for joel and me when I do his??

Sounds good Chris! I've been to autobarn on the weekend and spoke to their audio dude and he said that high pitched frequency doesn't have anything to do with the alternator. It's getting more serious now coz when I say eg. Open the window, turn on indicators....the needle drops way below 12V and its almost like the engine cuts out for a split second then comes back on again. This is really odd that my alternator was only rebuilt about 3 months ago.

Hopefully we can sort this out man! Probably can't do til weekend coz I live out in Hoppers Crossing which is a fair hike from Box Hill!

If your system is cranking your volts will fluctuate, that's normal. How bad is it. I fail to see how a sound system could impact an alternator to fail. You can at least isolate the noise to the amp by turning everthing off and disconnection the RCA leads from the head unit to the amp, turn the system on and see if there is noise. If there is then that will isolate the amp as the noise maker.

Now I'm not so sure if it is the head unit or amp.....

Keep in mind this has only started occuring over the last few weeks but has done it in the past (4 months ago) which then required an alternator rebuild.

Symptoms:

Voltage is normally happy at 12.6v-13v but sometimes will drop to around 10v when idle.

Needle drops to 12v when headlights, indicators and stereo are on

Sometimes the motor/electrics will turn off for a split second when electrics are activated (eg. windows, heater) even when travelling at 100km/h

My guess.........alternator regulator! Is there such thing as a voltage regulator?

What I'm trying to find out is what is causing the regulator to fail after it has recently been rebuilt........