I have installed my AVIC-Z3 into my C230 - 2007. I've worked on pre-face lift c230's with no problems installing AVIC units.
I used to work way back when in Car Audio Install (big box store) worked on may cars and in all my years... i've never had this problem.... ENGINE NOISE.
I have the worst case of engine noise out of this car. My cousin has a 2003 C230... preface lift car... pretty much same components.. without a single problem.
I've tried everything from checking voltage drops at all my ground points, factory ground, battery, ground at the amp & and ground at the factory harness. There is a 0.02 voltage drop between all those points... I have a fluke meter... super accurate... I have the amp grounded on the portion of the trunk between the two strut towers - solid reading ground.
The noise is coming from the AVIC Z3 ... can't figure out why, I had this headunit installed in my VW Passat 03... pulled it out when I traded it in for the benz.... the harnesses are all perfect, not kinks or nicks or anything.
when i plug in an ipod to the RCA's no noise or whine from the system... I've tried other rca's, I've run a 4awg ground wire directly to the amp from the battery... run power direct from the battery to the AVIC... still NOISE... Can't figure it out.
Has anyone else run into this when installing a full system - new amp - new speakers - new headunit ???
I'm running an Alpine PDX-5 (5channel amp) Pioneer Premier PRS Series Components in the front and standard in the back. I have a CAP on the amp also 1farad Monster Cap - Monster XLN RCA's - all the best of the best... and I have NOISE... Does anyone have a better grounding spot or a spot they used with success??? I don't want to go drilling all over the car.
I am ordering some PAC Noise Filters for POwer and RCA signals, buth those are just bandaids.... i want to fix the problem... in my 10 years of car audio... i've never heard this engine noise... and out of all people it happens to my own car !!!!!!!! I've even interfaced to common ground benz's, bmw's, volvo's, fords.... and never ever had engine noise....
Ladies and Gents...
Any help shedding some light on this situation would help drastically !!!
If anyone needs car audio gear, i'm a custom dealer - I'll hook you up !!!