Powertrain Control Module (PCM) C3 (NU3) Connector End View

Courtesy of GENERAL MOTORS CORP.
Connector Part Information		15460474 56-Way F Micro-Pack/064 Series (GY)
Pin	Wire Color	Circuit No.	Function
1-3	-	-	Not Used
4	TN/WH	3121	HO2S Low Signal
5	YE/BK	1227	TFT Sensor Signal
6	YE	492	MAF Sensor Signal
7	-	-	Not Used
8	BK/WH	3122	HO2S Heater Low Control - Sensor 2
9-10	-	-	Not Used
11	RD/BK	1230	AT ISS High Signal
12	YE	400	Signal High - Front
13-14	-	-	Not Used
15	GY	773	Transmission Range Switch Signal C
16-18	-	-	Not Used
19	PU	3120	HO2S High Signal
20-21	-	-	Not Used
22	YE	772	Transmission Range Switch Signal B
23	WH	776	Transmission Range Switch Signal P
24	WH	1804	TCC Release Switch Signal
25	-	-	Not Used
26	TN	472	IAT Sensor Signal
27-30	-	-	Not Used
31	WH	5268	Air Pressure Sensor
32	-	-	Not Used
33	L-GN	1222	1-2 Shift Solenoid Valve Control
34	BK/WH	771	Transmission Range Switch Signal A
35-38	-	-	Not Used
39	TN/BK	422	TCC Solenoid Valve Control
40-43	-	-	Not Used
44	PU	401	Signal Low - Front
45	-	-	Not Used
46	YE/BK	1223	2-3 Shift Solenoid Valve Control
47	RD/BK	1228	PC Solenoid Valve High Control (Sol. A)
48	BK	452	Low Reference
49	D-BU/WH	1231	AT ISS Low Signal
50	BK	2760	Low Reference
51	L-BU/WH	1229	PC Solenoid Valve Low Control (Sol. A)
52-56	-	-	Not Used