Jump to content
SAU Community

Recommended Posts

Why is it not ok to connect a head unit using a loom converter and just use the factory earth through the loom?

Is it really necessary to earth the head unit directly to the chassis?

Does this remove alternator noise not associated with the RCA's positioning?

Does an apexi super grounding system help to eliminate alternator noise?

A small 10cm long capacitor used inline with the power to my amp reduced the spark plug noise by 1/2 but did not completely eliminate it. Would getting one of those giant 30cm long lightning stick capacitors work for me? My battery is in the engine bay, does adding an extra battery in the boot in the way of the power to the amp help?

Link to comment
https://www.sau.com.au/forums/topic/135184-earthing-the-head-unit/
Share on other sites

Why is it not ok to connect a head unit using a loom converter and just use the factory earth through the loom?

Is it really necessary to earth the head unit directly to the chassis?

Does this remove alternator noise not associated with the RCA's positioning?

Does an apexi super grounding system help to eliminate alternator noise?

A small 10cm long capacitor used inline with the power to my amp reduced the spark plug noise by 1/2 but did not completely eliminate it. Would getting one of those giant 30cm long lightning stick capacitors work for me? My battery is in the engine bay, does adding an extra battery in the boot in the way of the power to the amp help?

I too am interested in this.

The guy who installed my system is asking for a day to try and get the noise out of it (free of charge - warranty) - and i simply cannot afford a whole day without my car at the moment (bloody work...).

Edited by nsanity

hi, when you get hums or whine noises that you hear from car audio systems, it is caused by electrical interference. most good head unit should not emits any of this audible noise. by saying that, your car's electrical system can also be the problem, old components may create a fault or picked up some sort of interference and this is put straight back through the car's power lines powering your head unit.

Old and tired batteries can cause this problem also.

a good car audio installer will use your factory wiring looms, why? because these cables are dedicated for your sound system and hence your head unit is not crossed wired to anything eles. also solder all contacts and heatshrink/taped all bare wires as it can easily pick up interference from current running through other wires.

noise suppressor can sometimes help and you can get them from Jaycar

i dont know if someone has mentioned it, but making sure your RCA's are running NOWHERE NEAR your power wires for amps and alike is vital. The best way is to run them down opposite sides of the car. Good quality RCA cables reduce alternator whine too as they're generally better shielded.

i dont know if someone has mentioned it, but making sure your RCA's are running NOWHERE NEAR your power wires for amps and alike is vital. The best way is to run them down opposite sides of the car. Good quality RCA cables reduce alternator whine too as they're generally better shielded.

actually if you use twisted pair leads it does help for noise rejection. the car is a noisey car unfortunately and what may work for one may not work on another.

I had this noise too, found that my RCA wires from the H/U to my amp in the boot was running too close to the earth wire coming from the battery to ground!!! just rerouted them away from the ground wire and noise gone.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Even more fun, leave all the ADAS stuff plugged in, but in different locations, hopefully avoid any codes!   And honestly, all these new cars with their weird electronics. Pull all the electronics out Duncan, and just shove an aftermarket ECU and if needed a trans controller in, along with a PDM. Make it run basic but race car styled!
    • To follow up a question from earlier too since I had the front bar off again (fking!) This is what is between the bumper and the drivers side wheel And this is the navigator side, only one thing but its a biggy! So basically....no putting coolers in the wheel arches without a lot of moving other stuff. Assuming I move to properly race prepping this car I'll take that job on and see how the computers respond to removing a whole bunch of ADAS modules
    • So I prepped the car for another track day on Wednesday (will be interesting to see coolant temps post flushing out and the larger reservoir, with a forecast of 3-14 being 20o cooler than last time I took it out). Couple of things to mention; since I am just driving the car and not taking a support vehicle, I took the rear seats out and just loaded the back up Team Trackday style. Look at all that space! To cover off removing the rear seat....it is weird (note the hybrid is probably different because it wouldn't have folding rear seats) Basically, you remove the lower seat base, very similar to a r series but it is a clip that pulls forward to release the base rather than it being bolted down. Easy Then, you need to remove the side section of the rear seat on each side. There is a 14mm head nut at the bottom of the side piece, the it slides upwards off a hook at the top to release; you also need to unhook the seatbelt from the loop at the top. Then the centre piece is weird. You need to release/fold the seats forward with the tab in the boot on each side From there, there are 2,x12mm headed bolts holding the rear of each seat to the folding bracket, under the trim between the rear seat and the boot (4x christmas tree clips there, they suck). The seat is out but you can see where the bolts attach to the bracket
    • As discussed in the previous post, the bushes in the 110 needed replacing. I took this opportunity to replace the castor bushes, the front lower control arm, lower the car and get the alignment dialled in with new tyres. I took it down to Alignment Motorsports on the GC to get this work done and also get more out of the Shockworks as I felt like I wasn't getting the full use out of them.  To cut a very long story short, it ended up being the case the passenger side castor arm wouldn't accept the brand new bush as the sleeve had worn badly enough to the point you could push the new bush in by hand and completely through. Trying a pair of TRD bushes didn't fix the issue either (I had originally gone with Hardrace bushes). We needed to urgently source another castor arm, and thankfully this was sourced and the guys at the shop worked on my car until 7pm on a Saturday to get everything done. The car rides a lot nicer now with the suspension dialled in properly. Lowered the car a little as well to suit the lower profile front tyres, and just bring the car down generally. Eternally thankful for the guys down at the shop to get the car sorted, we both pulled big favours from our contacts to get it done on the Saturday.  Also plugged in the new Stedi foglights into the S15, and even from a quick test in the garage I'm keen to see how they look out on the road. I had some concerns about the length of the LED body and whether it'd fit in the foglight housing but it's fine.  I've got a small window coming up next month where I'll likely get a little paint work done on the 110 to remove the rear wing, add a boot wing and roof wing, get the side skirt fixed up and colour match the little panel on the tail lights so that I can install some badges that I've kept in storage. I'm also tempted to put in a new pair of headlights on the 110.  Until then, here's some more pictures from Easter this year. 
    • I would put a fuel pressure gauge between the filter and the fuel rail, see if it's maintaining good fuel pressure at idle going up to the point when it stalls. Do you see any strange behavior in commanded fuel leading up to the point when it stalls? You might have to start going through the service manual and doing a long list of sensor tests if it's not the fuel system for whatever reason.
×
×
  • Create New...