Car power issue - amp works indoors, doesn't work in the car

[Willydk]

So hopefully my last thread about this //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif

Long story short:

Tested my amp indoors, tested speaker indoors - works perfectly fine.

When I power it up in my car, using exactly the same setup as indoors(phone rca) it powers up but does not output speaker voltage.

I'm 100% sure that it's power/ground issue. But what is wrong?

I'm using ~1meter of "Car Hi-Fi cable, 10mm2, 60A" for power, and same type of cable for ground.

The car is bmw E46, I tried wiring ground to the same spot where battery's ground cable is connected, and also on a bolt in upper trunk area.

What could be wrong?

Click to read more...