For those who haven't figured this out, the mute wire from a D3 is needed to perform muting of the OnStar system. Most wiring adapters use a work around that actually powers off the unit when OnStar is activiated if the mute wire is not hooked up. If you want to truly mute OnStar without turning the unit off, you need to do the following:

1-Do not move the mute wire as instructed in the bypass

2-Purchase a DEI antenna on eBay (<$10) which contains 6 pins identical to those used in the D3 wiring harness.

3-Use the new pin to perform the bypass instead of moving the mute wire.

4-Connect the mute wire to the wiring harness following mfg instructions (you usually have to cut another loop wire to tell the harness to use the mute instead of turning the unit off).

Good luck - I hope this helps

This has been posted before, but nicely written. I had to do this a couple years ago and it worked like a charm.

ok i am really dumb any pics or slower step by step need you to break it down to Barney level

ok never mind i got it i took my dash plate appart and looked in real good and found out when i had my install of my audio video junk they put in a pac controler for the onstar, needless to say the mute wire was never hooked to anything so i did the switch and spliced my green wire to my mute slapped it into a pregrounded wire and walah bypass done took about 10 min to do the mod found out that my dimmer for the nighttime works i just have to flick the switch i wish it would automatically come on when the head lights come on due to me having blue leds in the hood scoop but hopefully the bad boys in blue wont notice