Adding the Factory 12 Disc CD Player (2000+ Bonneville)
Although I have tried to ensure the information provided is complete and accurate, errors or omissions may exist. If I find or am made aware of any, I will post corrections as applicable.
The 12 disc player connects to an audio input on the rear of the factory head unit. Depending on the model year of the vehicle, an *-Band receiver (XM Tuner) may share the same input. OnStar also connects to the radio but has a separate input which is not shared with other devices.
The 12 disc player is a Class 2 device. Since it connects to the “network” of other class 2 devices (including the radio HU), it can be controlled by receiving signals over this data bus. Control signals include such commands as changing which disc or track is playing. Since the input may be shared with the *-Band receiver, the 12 disc player can be commanded to turn on or off its audio output. The radio can also receive signals from the 12 disc player such as which disc and track are playing and whether a cartridge is installed.
This diagram illustrates the basic concept of the Class 2 Serial Data Bus:
About the wiring:
In this section, part numbers of terminals, connectors and connector housings are all Delphi Packard Electric numbers. In many cases, these are the same as GM numbers. Regardless, your local GM Parts Department may not be able to look these up as a valid item. The Service Department will have a connector repair kit which will contain all terminals shown here. It is up to each individual Service Department as to whether they will sell these items as parts.
There are a total of 8 connections made at the rear of the changer. These are shown on the diagram below:
The connector which plugs into the back of the 12 Disc Player is P/N: 12047531. It is available through you GM Parts Department.
You will also need the following terminals in order to populate the above connector:
GM has used 0.35mm2 wire (SAE 22 gauge) for all conductors.
To prevent electrical noise, the audio conductors are wrapped with a foil shield. A bare conductor (drain wire) travels on the outside of the shield. Only ONE end of the drain is connected (at the 12 disc player). The other is a blunt cut just before the audio wires enter the main radio HU connector. For the purpose of this procedure a 3 conductor, 22 gauge shielded audio cable with a drain wire should be used (below).
For the Bonneville, GM has used the following colour coding for the 12 disc player circuit:
Battery Positive Voltage – ORN (Orange)
Ground – BLK/WHT (Black w/ White Tracer/Stripe)
Class 2 Data – PPL (Purple)
For consistency, it is recommended that this colour code be used.
Making Electrical Connection into the Vehicle:
The following terminals are required to connect into the factory splice pack (Ground) and the power distribution block (Positive Battery Voltage).
*** It is recommended that you disconnect the battery prior to making connection into the vehicle wiring harness. Damage, personal injury and/or unnecessary repairs may result. ***
Connecting the Ground:
Since a BLK/WHT wire is often not available, solid BLK is the next best option. There is a splice pack located in the trunk behind the right side trim panel. This is where the factory installed 12 disc player is grounded. It doesn't matter which vacant cavity is used in this instance.
Connecting the Battery Positive Voltage (+12 VDC):
This connection, at the factory, is made in the rear power distribution block. Use of the factory fuse should be possible. Many vehicles, even those without the factory installed changer will have a fuse pre-installed. You can check this by looking at the fuse reference label on the cover for the fuse block.
Connecting into the Class 2 Serial Data Bus:
PPL is used for the data lines between all Class 2 Serial devices (varies with other vehicle lines). PPL is not exclusive to Class 2 Data and it can’t be assumed that any PPL wire will be a part of this data bus. Where the connection is made into the Class 2 Data Bus isn’t important, only that it be made correctly. The wiring harness at the RCDLR (Remote Control Door Lock Receiver) is one of the easiest and most convenient. The RCDLR is located in the trunk, below the rear deck on the LEFT side.
A splice can be made into the wiring at the RCDLR connector in order to avoid having to try and locate difficult to find connectors. This is easily done by anyone with some degree of experience with a soldering iron.
To accomplish this:
1. Unplug the 4 conductor connector at the RCDLR (blue in colour).
2. Peel or cut back the tape wrapping the wires to expose about 4 inches of wire.
3. Cut one of the two PPL wires. Strip approximately 0.5” of insulation from each wire end.
4. Place a piece of heat shrink tubing onto each of the wires large enough to insulate the connection once it has been soldered.
5. Attach one PPL wire to each of these ends long enough to reach behind the 12 disc player. Routing is easiest by attaching these to the support running across the back of the trunk compartment.
6. Solder each of the connections. Carefully using a heat gun, shrink the tubing over the exposed connection.
7. Re-tape the wiring with the new conductors in place.
8. Plug-in the connector to the RCDLR.
Pictures of this process will be added soon…
Watch for PART 2 Soon!!!