Vehicle Communication Unit (VCU) Coonector End View

Courtesy of GENERAL MOTORS CORP.
Connector Part Information		205207-1 25 - Way F (BLK)
Pin	Wire Color	Circuit No.	Function
1	DK GRN/ WHT	2507	Audio Transmit Signal
2	-	-	Not Used
3	BLK	2520	Transceiver Low Reference
4	ORN	2540	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	BLK	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	BLK/WHT	1235	Audio Low Reference
25	-	-	Not Used