ground wire and am radio
 

i have a stupid ?. I listen to AM radio sometimes and i have always not been able to get a good signal with aftermarket stereos. when connecting the ground on the radio should you connect it to the ground on the harness, or should you ground it to the car. thanks for your feedback.

matt

It is always a good idea to chassis ground your headunit. While the stock ground will work the aftermarket units usually draw more current and could use a better ground.

yah, as speedfreak mentioned, just use the chassis ground. in fact, the screws that mount the HU bracket onto the frame can be used as ground. it's a pretty clean signal.

You mean the silver screw's right?

yep, the silver screws that mount to the metal bracket. not the black screws to mount the trims as the nut clamps for those on the other end is not grounded.

Awesome thanks!

a good way to check for ground is use your multi-meter in volt mode, place one of the probes on a known ground, then the other other probe on the candidate metal. if the volt drops to zero and stays there, that is a clean ground.

if the volt fluctuates near zero, it's got noise. or if it doesnt go anywhere near zero, that is ungrounded.

Ok.. A couple more questions..

1. I just installed a new radio yesterday and one of the wires was left unconnected.. It was orange/white (or maybe orange/black, I forgot now) it said "dimer" on it.. I just capped it and left it.. Is that ok?

2. There was a blue wire coming from both the antenna adapter and the harness.. I connected them together (no connection to the new unit) That ok?

3. Last thing.. Would me not grounding it correctly cause radio interference (as if the stations are going out of range)? I'm getting that now.. Going to take it apart again to ground it like you said just curious as to whether that will fix it when I do.

Thanks for the help!

The orange/white dimmer wire would dim the stereo lights with your dash lights. Perfectly fine to leave off.
The blue wire you speak of is the remote turn on for the powered antenna unit. it should be connected to the blue lead off of your head unit. this may be your interference issue. the antenna is not powering up.
As for grounding being the issue for radio interference, like I posted in your other thread, not likely the culprit.

Thanks! That extra wire had me a bit worried