| Table 1: | OnStar® Button Assembly | 
| Table 2: | OnStar® Microphone | 
| Table 3: | Vehicle Communication Unit (VCU) | 
| Table 4: | Vehicle Interface Unit (VIU) - C1 | 
| Table 5: | Vehicle Interface Unit (VIU) - C2 | 
 
 | |||||||
|---|---|---|---|---|---|---|---|
Connector Part Information  | 
 
  | ||||||
Pin  | Wire Color  | Circuit No.  | Function  | ||||
A  | LT GRN/BLK  | 2515  | Keypad Supply Voltage  | ||||
B  | DK GRN/ WHT  | 2514  | Keypad Signal  | ||||
C-D  | --  | --  | Not Used  | ||||
E  | ORN/BLK  | 2518  | Keypad Low Reference  | ||||
F  | YEL/BLK  | 2516  | Keypad Green LED Signal  | ||||
G  | BRN/WHT  | 2517  | Keypad Red LED Signal  | ||||
H  | --  | --  | Not Used  | ||||
 
 | |||||||
|---|---|---|---|---|---|---|---|
Connector Part Information  | 
 
  | ||||||
Pin  | Wire Color  | Circuit No.  | Function  | ||||
A  | BARE  | 1705  | Drain Wire  | ||||
B  | GRY  | 655  | Cellular Telephone Microphone Signal  | ||||
 
 | |||||||
|---|---|---|---|---|---|---|---|
Connector Part Information  | 
 
  | ||||||
Pin  | Wire Color  | Circuit No.  | Function  | ||||
1  | DK GRN/ WHT  | 2507  | Audio Transmit Signal  | ||||
2  | --  | --  | Not Used  | ||||
3  | GRY  | 2520  | Transceiver Low Reference  | ||||
4  | ORN  | 2240  | Battery Positive Voltage  | ||||
5  | PPL/WHT  | 2513  | Ignition ON Signal  | ||||
6  | BRN/WHT  | 2506  | Audio Return Signal  | ||||
7-10  | --  | --  | Not Used  | ||||
11  | LT BLU/BLK  | 2512  | OnStar Serial Data (+)  | ||||
12  | DK BLU/ WHT  | 2511  | OnStar Serial Data (-)  | ||||
13  | --  | --  | Not Used  | ||||
14  | BARE  | 1792  | Drain Wire  | ||||
15  | GRY/BLK  | 2508  | Microphone Signal  | ||||
16-17  | --  | --  | Not Used  | ||||
18  | TAN/BLK  | 2510  | OnStar Serial Data Return  | ||||
19-23  | --  | --  | Not Used  | ||||
24  | LT BLU  | 1235  | Audio Low Reference  | ||||
25  | --  | --  | Not Used  | ||||
 
 | |||||||
|---|---|---|---|---|---|---|---|
Connector Part Information  | 
 
  | ||||||
Pin  | Wire Color  | Circuit No.  | Function  | ||||
A1  | --  | --  | Not Used  | ||||
A2  | GRY  | 2289  | Rear HVAC/Audio Class 2 Serial Data  | ||||
A3-A5  | --  | --  | Not Used  | ||||
A6  | BLK/WHT  | 372  | Remote Radio Audio Output (-)  | ||||
A7  | --  | --  | Not Used  | ||||
A8  | BRN/WHT  | 367  | Remote Radio Left Audio Signal  | ||||
A9  | BARE  | 814  | Drain Wire  | ||||
A10  | LT BLU  | 1235  | Audio Low Reference  | ||||
A11  | BRN  | 2506  | Audio Return Signal  | ||||
A12  | DK GRN  | 2507  | Audio Transmit Signal  | ||||
A13  | BARE  | 1792  | Drain Wire  | ||||
A14  | GRY/BLK  | 2508  | Microphone Signal  | ||||
A15  | --  | --  | Not Used  | ||||
A16  | ORN  | 2240  | Battery Positive Voltage  | ||||
B1-B8  | --  | --  | Not Used  | ||||
B9  | GRY  | 655  | Cellular Telephone Microphone Signal  | ||||
B10  | BARE  | 1705  | Drain Wire  | ||||
B11  | TAN  | 2510  | OnStar Serial Data Return  | ||||
B12  | DK BLU  | 2511  | OnStar Serial Data (-)  | ||||
B13  | LT BLU  | 2512  | OnStar Serial Data (+)  | ||||
B14  | GRY  | 2520  | Transceiver Low Reference  | ||||
B15  | PPL  | 2513  | Ignition ON Signal  | ||||
B16  | --  | --  | Not Used  | ||||
 
 | |||||||
|---|---|---|---|---|---|---|---|
Connector Part Information  | 
 
  | ||||||
Pin  | Wire Color  | Circuit No.  | Function  | ||||
E1-E3  | --  | --  | Not Used  | ||||
E4  | DK GRN/WHT  | 2514  | Keypad Signal  | ||||
E5  | YEL/BLK  | 2516  | Keypad Green LED Signal  | ||||
E6  | LT GRN/BLK  | 2515  | Keypad Supply Voltage  | ||||
E7-E15  | --  | --  | Not Used  | ||||
E16  | ORN  | 2740  | Battery Positive Voltage  | ||||
F1  | BLK  | 1550  | Ground  | ||||
F2-F3  | --  | --  | Not Used  | ||||
F4  | ORN/BLK  | 2518  | Keypad Low Reference  | ||||
F5-F8  | --  | --  | Not Used  | ||||
F9  | BRN/WHT  | 2517  | Keypad Red LED Signal  | ||||
F10-F16  | --  | --  | Not Used  | ||||