Hey guys, remember Me? probably not but anyways, Ive just bought a Pioneer Gm-6100-f 600W 4ch Amp, the amp works fine and everything until I switch my key over to start and the fuel pump comes on, the rear speakers start to whine with the motor. BUT as soon as the rear RCA plug ( its on a little cord on the back of new pioneer decks) touch the metal bracket that holds the H/u, the engine noise stops. Does this mean my 4 month old H/U is kaput?
Ive tried everything, completely new paint free ground pionts, upgraded + and - cables to 4G new DNA rca`s
. I havent tried a ground loop isolater or any of those types of devices yet.
:rant: :rant: :rant: :rant: :tantrum:

RCA's in the headunit arent grounded properly or have blown from incorrect installation - ie, leaving your battery connected when plugging in the rca leads. (happened on my pioneer 5550-MP)


Take it in to get fixed.

damnit, Could it possibly be anything else at all? cos I dont wanna have to wait for the H/U to come back plus having to pay for it to be repaired.
Everything was unplugged. I.e battery was on the ground ready to be relocated. nothing was unplugged with the battery still in the car ever, so I dunno how it could have damaged the RCAs

Maybe I`ll try another H/U see if its still there or not, if it`s still there Im gunna curl up in a corner somewhere and think happy thoughts,.....
Ive been fighting with this H/U since I bought it

This H/U is a 5750MP Pioneer. everything else is pioneer except my sub which is clarion.

Before you take the headunit in for someone to have a look at it, be sure to eliminate the possibility of an interference in the rca's from the car (as opposed to the headunit).

You can make sure it's the headunit at fault by unplugging the rca's from the back of the headunit keeping them in the same area (not touching anything). Keep the rca's plugged in to your amplifier at the other end and turn the ignition on. If the sound is still there then it is obviously not your headunit but a form of induced noise.

Listen carefully and try to judge what tone the noise is at eg; does the frequency change with engine rpm? Or is it a steady 1 kHz tone (which is often emitted from the engine management system) or a fluctuating tone (as found in the fuel pump or aircon?)

I'm interested to know more about the RCA preamp output being at fault. Often when the ground on rca's go live the noise is quite extreme... Are these new headunits with higher voltage outputs masking serious problems I wonder?

Altenator whine

http://www.aussiemagna.com/forums/showthread.php?t=24067