GMCO hookup ?
Thread Starter
Racer
Joined: Jan 2007
Posts: 276
Likes: 1
From: The Bronx
GMCO hookup ?
How are things going folks?
Finally installed a Clarion NAV unit using Peripheral's GMCO. Everything went smooth until I turned on the car and got the dreaded whine.
I grounded the head unit to the GMCO's black wire. NOT to a chassis ground.
Should I have grounded both the GMCO and NAV to a chassis ground?
I removed the factory BOSE amp and speakers. I don't know if that matters.
Thanks in advance.
Finally installed a Clarion NAV unit using Peripheral's GMCO. Everything went smooth until I turned on the car and got the dreaded whine.
I grounded the head unit to the GMCO's black wire. NOT to a chassis ground.
Should I have grounded both the GMCO and NAV to a chassis ground?
I removed the factory BOSE amp and speakers. I don't know if that matters.
Thanks in advance.
Tech Contributor
Joined: May 2003
Posts: 7,035
Likes: 134
From: North Augusta, SC
On my D3 setup I have both the GMCO and the HU grounded to the stock radio ground wire, and they're both powered by the hot wire in the stock radio plug, but I also have a noise filter connected to those power wires and two ground loop isolators on the HU RCA outputs. No whine in my setup 
It's also possible your problem could be due to the way you have the amp power wires and the RCA's run, or the way the amp power or ground is connected.
Do some experimenting and answer these questions for us....
Do you have any whine if you use the radio without the engine running?
Do you have any whine with the engine running and the radio on but the volume muted (rev the engine a few times)?
Does the whine change pitch with the RPM of the engine?
Does the whine change pitch depending on how loud you play the radio (constant RPM)?
What is your amp setup?
It's also possible your problem could be due to the way you have the amp power wires and the RCA's run, or the way the amp power or ground is connected.
Do some experimenting and answer these questions for us....
Do you have any whine if you use the radio without the engine running?
Do you have any whine with the engine running and the radio on but the volume muted (rev the engine a few times)?
Does the whine change pitch with the RPM of the engine?
Does the whine change pitch depending on how loud you play the radio (constant RPM)?
What is your amp setup?
