My Metra GMOS-04 Instructions tell me to connect the mute (brown) wire to the yellow/black mute wire of the D3. Do i still do this if i'm doing the bypass?

It also says to connect the gmos-04 green wire to the D3 brake wire. Do this too if bypassing or no?

Also, the gmos-04 harness has the blue/pink vss and green/purple reverse wires already so does that mean i can just directly connect it to the corresponding wires from D3 or do i still have to tap into the trucks vss and reverse wires?

My truck is an 04 Chevy Silverado with Bose & Onstar

Thank You.

In order:

If you want to do the bypass and don't care about OnStar automatically muting the stereo, then don't bother connecting to the yellow/black and do the bypass normally. Otherwise use another wire for the bypass from that harness.

If you're doing the bypass, hook the brake wire up to the radio GROUND, not the GMOS

Yes, you should be able to use the VSS and Reverse wires from the GMOS. Just make sure that they are what you think they are, don't just go by 'they match the color of the Pioneer harness'. Check the documentation to make sure they are what they look like.

Ok thanks guys. Also, I was driving and played a movie a while ago to test the bypass and it worked for a few minutes then gave me a warning about the brake wire not being connected properly. I just grounded the brake wire and and didn't connect it to the trucks ebrake wire. Is this that right or must i connect it to the trucks ebrake also?

I had that happen to me prior to doing the 'mute wire' bypass. Once I did that part of the bypass I never saw it again.

Others could chime in with their experiences tho..