Making custom Denali CD changer harness, HELP!

Hi all,

I've had some trouble with connectivity with my Denali CD changer t-tapped into my factory radio.  So I've since removed the t-taps and disconnected the changer entirely (temporarily) and am building a new go-between harness that will be assembled/tested entirely outside of the truck and then installed between the factory radio + harness.

What I'm doing is taking the piggyback harness from a USA-Spec under-seat CD changer for 03+ GM applications and combining it with the "half cable" that came with my Denali CD changer (from JP customs) that was formerly t-tapped directly into the factory harness.

BTW, for anyone interested in doing this, the part number for the USA-Spec harness is "CAS-G7i"...got mine as discountcarstereo.com for like $20-30.

I'm all set to wire this up and was using this diagram from Linda's mega-thread on nav/changer installs:


But I ran into one issue that has caused me mild concern.  First, note that the CAS-G7i harness is doing the EXACT same thing I want to do.  But it has DIFFERENT wires tapped than the ones shown above.

On the 12-pin connector, the three audio pins are tapped (K, J, H) as shown in the diagram.  But "G" is also tapped.

On the 24-pin connector, B1 and A12 are tapped, but A1 is NOT.  Instead, B2 is tapped. 

At this point, I'm tempted just to undo all the work they've done to this harness, and start from scratch based on the diagram. 

Here is a pic of what I'm working with:

need more info pleaze.. do you have xm and onstar? how will you connect this harness the way i understand you are making a duel harness that will connect to xm and the cd changer instead of tapping the radio wires? im right? if you get this to work id be interested in one if you can make on thanks

moosc said:

need more info pleaze.. do you have xm and onstar? how will you connect this harness the way i understand you are making a duel harness that will connect to xm and the cd changer instead of tapping the radio wires? im right? if you get this to work id be interested in one if you can make on thanks

Click to expand...

I have both XM and OnStar.  This harness will plug into the back of the radio, and the factory harness will plug in to it.  All the factory connections pass straight through.  The idea behind this harness is to allow me to tap into it without (further) screwing up the factory harness.  I had previously tried t-taps into the factory harness for this CD changer, but wound up with connectivity issues.  I've since disconnected those and don't want to cause additional injury to the factory harness by trying again.

A1 is needed for the class II data, unless it tapps elsewhere.

Here's a factory diagram:

Click it to enlarge.



Head unit connector 1:



---

Head unit connector 2:



This & some other reference: HERE.

HTH!

Had to correct some links for a member.

sperry said:

A1 is needed for the class II data, unless it tapps elsewhere.

Here's a factory diagram:

Click it to enlarge.



Head unit connector 1:

---

Head unit connector 2:

This & some other reference: HERE.

HTH!

Click to expand...