Ok, so I put in a new pioneer head unit in my car and used the GMOS-LAN-04 wiring harness cause it's a 2007 without onstar but pioneer sound system. The problem is the door chime is loud and so is the blinker sound, anyway to get around that?

 

Humm this happened to my car when the dealer replaced my factory radio, they didnt have the software to turn it down when they replaced the software so they turned it off lol!

 

on the harness there is a box with a philips screw head in there. turn in counter clockwise to lower the doorchimes and blinker. i had the same problem, easy fix though

 

Actually the blinker volume is supposed to be controlled through the jumpers that are on the other side of the dial.
However when I changed mine it didn't do sh*t, turning the screw on the side of the box did so that goes to show you what good comes from reading the instructions.
Carefull how far down you turn that screw, it also controls the over all volume for the stereo.

 

Where is the harness on the back of the radio?

 

yes, it plugs into the aftermarket radio, GM-LAN-04 is what i have

 

Will it adjust the chime with the factory radio? Is Gm LAN 4 factory?

 

No. The adapter harness is only used when installing an aftermarket radio.