Hello all,

I've recently had a Pioneer DVD head unit fitted, and I came to notice that when I have the cars headlights on, dipped or otherwise, there is a high pitch whining noise produced.

It was also present with another pioneer headunit I had, I thought it maybe the headunit itself, hence the change.

I think it is a grounding issue, but then why would it only come one when I turn the lights on and not all the time?

Could it be connected to the light dimmer control? or the lights grounding point?

Anyone know, its starting to drive me mad, as I can't help but listern to the whine rather than the music.

 

Sounds like a bad earth. Do you have any amps connected? if so, make sure that these are all earthed to the same point. If you don't have any amps, try connecting the unit to a new earth point, using 8awg wiring.

 

As above and try disconnecting the dimmer control to see if that makes a difference.

Take some wet and dry and rough the contacts on your earths.

Also are your speaker cables near any lives for the lights???? try shielding them or moving them away. If they must cross lives or RCA's try to do it at right angles to minmise the interference.

Dave

 

Is it present when the engine isn't running? If not, does it change in pitch or volume when the engine revs change?

It could be alternator whine. If so, have the alternator checked, or see an ICE dealer for ideas as to how to suppress it.

Alcazar

 

Hi all, thanks for the advice I shall look into that tomorrow.

As for amps I've got three of them. All earted to the same point with 8 gauge gold wiring.

Where can I find the dimmer control? Thats sounds likely as the problem asrises when the lights are put on.

 

the ground wire should be as short as you can and that will be a problem if thie are all togather without using a block..

 

In total the earth wires are less than 10cm, I'm not able to get them any shorter. Its a very good ground so I don't think that is the problem. Well the ground on the amps anyone. As for the headunit is't self I'm not sure.

What I have noticed is the noise is only there when I have my ipod playing via my Pioneer Ipod adaptor, this doesn't have a earth, it takes it's earth from the headunit. and the CD player and cd changer don't have this whining noise I can't see it being that either.

My favorite is the alternator problem.

I'm gonna listern to see if the noise is there when the car is on ignition.

 

Right. The noise is only there when I use the ipod adaptor when the lights are on side lights or headlights.

It does it when the engine is running and when the engine is off.

From that I think its linked directly to the lights.

Someone mentioned undoing the dimmer switch, how do I do that and where do I find it. Is it somehting I can undo and have no side effects or does it need to be connected at all times?

 

Tried all the above advice and noise is still there.

 

Put a filter on the alt...or put a inline filter on the deck it is a bad ground..You can also put a earthing kit on the car it will help..

 

if u remove the headunit is there a wire which has illum written on it,
if so cut this wire temporarily, see if this cures the problem.
also try running a earth from the car to the casing of the radio it self,
these are justa couple of simple tests to do which may help
chris

 

Cheers Guys, not sure if this will help as the problem is only there when I use the iPod, not when I use the headunit CD player, CD changer, or radio.

If it was a groudng issue would all four be effected? None the less its really doing my head in so I'll try it and see.

I've had the iPod unit out and tried it in my brothers car and nothing, so I'm sure it's not the iPod unit itslef.

Also I've had a minidisc changer hooked up to the aux out in the iPod's place in case it was the AUX out that was the problem, and nothing no a dickie bird.

I'm at a total loss.

 

The noise you are experiencing is called engine noise and is normally common because you are running RCA leads close to the power leads going to your amplifiers.

You normally need to run audio down one side of the car and power down the other so the 2 are far apart from each other.

As for it just happening when just using your iPod I don't know but if the above is true sort that out then see if it fixes it.

 

Already thought about that my RCA go down the left and the seakers cable down the right with the power and remote wires separately going down the middle of the car.

 

I may be clutching at straws here...... but your head unit live wire (or switch live) doesnt feed from your lights at the fuse box does it??

Sounds like you've exhausted all other possibilites.
Just a thought

Dave

 

It's got to be something to do with my lights, so its a possibility.

I've not looked into that yet. I'll take a look, cheers for that.

 

I actually managed to sort my whine out for a while, so I'll list the things I did as they might help you. My symptoms also got worse with lights on, I could hear it more when the AC compressor kicked in, etc.

Engine bay:

1. Supplemented the earth between chassis and battery with 4AWG cable - used same earth points as standard and left the standard cable in as well for good measure (the standard cable is a little weedy anyway, so you could *probably* remove this completely)

2. Same as point 1 for the cable that goes from the block to the negative pole of the battery.

Boot:

3. In boot, made one good earth point that I wired up to a connection block (one of those maplin's ones) so as to ensure that the amps have the same earth point.

Head unit end:

4. Ran a new earth from the battery to the front of the car, connected to distribution block.

5. Ran a new positive feed from battery to front (again, into distribution block).

6. Spliced an ignition and illumination feed off from the centre console somewhere (might have been cigarette lighter for ignition and something else for illumination)

7. Created new *isolated* illumination and ignition feeds from the standard wiring ones using relays (they're about 1-2 pounds each in Maplin's from memory).

8. New ISO loom to hook everything up to stereo.

9. Grounded stereo chassis to the new earth point up front.

Now, when I had done all the above, the alternator whine was gone.

Unfortunately, I initially forgot to connect the antenna power feed, and once I hooked that up, the whine was back (I suspect the antenna is powered from the old crappy wiring, but I don't know where to find the unit).

So, it *is* possible to get rid of the whine, but some cars are just a pain in the bum when it comes to finding the cause.

Also, you may want to upgrade the wire that runs from the alternator to the positive pole on the battery. I didn't do this, as my stereo isn't drawing huge amounts of current (I've only got about 300W RMS and I hardly ever play the music loud anyway).