Engine Control Module (ECM) Connector End Views

Engine Control Module (ECM) C1

Courtesy of GENERAL MOTORS CORP.
Connector Part Information		15491996 56-Way F Micro-Pack 64 Series, Sealed (BU)
Pin	Wire Color	Circuit No.	Function
1	TN/WH	2500	High Speed GMLAN Serial Data Bus (+)
2	TN	2501	High Speed GMLAN Serial Data Bus (-)
3	-	-	Not Used
4	BN/WH	419	MIL Control
5-6	-	-	Not Used
7	BN	1271	Low Reference
8	PU	1272	Low Reference
9	-	-	Not Used
10	YE	5991	Powertrain Relay Coil Control
11-12	-	-	Not Used
13	YE/BK	625	Starter Enable Relay Control
14	PK	839	Ignition 1 Voltage
15	YE	710	Class 2 Serial Data
16	D-GN	1049	Class 2 Serial Data
17	GY	397	Cruise Control On Switch Signal
18	PK	1020	Ignition 0 Voltage
19	PK	439	Ignition 1 Voltage
20	OG	240	Battery Positive Voltage
21	D-GN/WH	817	Vehicle Speed Signal
22	D-BU	1161	APP Sensor 1 Signal
23	D-BU	2364	Cooling Fan Speed Signal
24	D-GN	890	Fuel Tank Pressure Sensor Signal
25	-	-	Not Used
26	RD/BK	380	A/C Refrigerant Pressure Sensor Signal
27	D-BU	84	Cruise Control Set/Coast Switch Signal
28	-	-	Not Used
29	TN	1274	5-Volt Reference
30	GY	2700	5-Volt Reference
31	GY	2709	5-Volt Reference
32	L-BU	1320	CHMSL Supply Voltage
33	GY/BK	87	Cruise Control Resume/Accel Switch Signal
34	-	-	Not Used
35	WH/BK	1164	5-Volt Reference
36	WH/BK	2366	Cooling Fan Clutch Control
37	PU	1589	Fuel Level Sensor Signal
38-40	-	-	Not Used
41	L-BU	1162	APP Sensor 2 Signal
42-44	-	-	Not Used
45	D-GN/WH	465	Fuel Pump Relay Control
46	PU	420	TCC Brake Switch/Cruise Control Release Signal
47	-	-	Not Used
48	WH	121	Engine Speed Signal
49	YE/BK	1827	Vehicle Speed Signal
50	-	-	Not Used
51	OG/BK	1786	Ignition Lock Cylinder Control Actuator Signal
52	PU	806	Crank Voltage
53	-	-	Not Used
54	WH	1310	EVAP Canister Vent Solenoid Control
55	BK	2751	Low Reference
56	-	-	Not Used

Engine Control Module (ECM) C2

Courtesy of GENERAL MOTORS CORP.
Connector Part Information		15481009 73-Way F GT 280 Series, Sealed (BK)
Pin	Wire Color	Circuit No.	Function
1	L-GN	3212	HO2S Heater Low Control - Bank 2 Sensor 1
2	BK/WH	3113	HO2S Heater Low Control - Bank 1 Sensor 1
3	-	-	Not Used
4	D-BU/WH	878	Fuel Injector 8 Control
5	BK	1744	Fuel Injector 1 Control
6	L-GN/BK	1745	Fuel Injector 2 Control
7	RD/BK	877	Fuel Injector 7 Control
8	L-BU/BK	844	Fuel Injector 4 Control
9	PK/BK	1746	Fuel Injector 3 Control
10	BK/WH	845	Fuel Injector 5 Control
11-12	-	-	Not Used
13	YE/BK	846	Fuel Injector 6 Control
14	YE/BK	1868	Low Reference
15	PK/BK	632	Low Reference
16	BN	2129	Low Reference
17-19	-	-	Not Used
20	OG/BK	469	Low Reference
21	BK	2755	Low Reference
22-23	-	-	Not Used
24	TN/WH	332	Oil Pressure Sensor Signal
25	-	-	Not Used
26	BN/WH	633	CMP Sensor Signal
27-28	-	-	Not Used
29	PU	486	TP Sensor 2 Signal
30	-	-	Not Used
31	D-GN	485	TP Sensor 1 Signal
32-34	-	-	Not Used
35	GY	2704	5-Volt Reference
36	BK/WH	1704	Low Reference
37	GY	2705	5-Volt Reference
38-40	-	-	Not Used
41	L-BU/BK	1688	5-Volt Reference
42	-	-	Not Used
43	L-GN	1867	12-Volt Reference
44	RD	631	12-Volt Reference
45	GY	23	Generator Field Duty Cycle Signal
46	L-GN	432	MAP Sensor Signal
47	-	-	Not Used
48	PU/WH	1665	HO2S High Signal - Bank 1 Sensor 1
49	TN	1664	HO2S Low Signal - Bank 1 Sensor 1
50	D-GN/WH	428	EVAP Canister Purge Solenoid Control
51	PU	1666	HO2S High Signal - Bank 2 Sensor 1
52	BK	2761	Low Reference
53	RD	2127	IC 7 Control
54	PU	2121	IC 1 Control
55	YE	410	ECT Sensor Signal
56	RD	225	Generator Turn On Signal
57	L-BU/WH	2126	IC 6 Control
58	D-GN/WH	2124	IC 4 Control
59	D-GN	2125	IC 5 Control
60	BN	582	TAC Motor Control - 2
61	L-BU	2123	IC 3 Control
62	D-BU/WH	1869	CKP Sensor Signal
63	YE	581	TAC Motor Control - 1
64	BN/WH	2130	Low Reference
65	PU/WH	2128	IC 8 Control
66	RD/WH	2122	IC 2 Control
67	-	-	Not Used
68	D-BU	496	Knock Sensor 1 Signal
69	GY	1716	Low Reference
70	TN	1667	HO2S Low Signal - Bank 2 Sensor 1
71	GY	2303	Low Reference
72	L-BU	1876	Knock Sensor 2 Signal
73	BK	450	Ground

Engine Control Module (ECM) C3

Courtesy of GENERAL MOTORS CORP.
Connector Part Information		15481007 56-Way F Micro 64 Series, Sealed (GY)
Pin	Wire Color	Circuit No.	Function
1	-	-	Not Used
2	BN	2391	HO2S Heater Low Control - Bank 1 Sensor 2
3	RD/WH	3223	HO2S Heater Low Control - Bank 2 Sensor 2
4-10	-	-	Not Used
11	YE	492	MAF Sensor Signal
12-17	-	-	Not Used
18	TN/WH	1669	HO2S Low Signal - Bank 1 Sensor 2
19	PU/WH	1668	HO2S High Signal - Bank 1 Sensor 2
20	PU	1670	HO2S High Signal - Bank 2 Sensor 2
21	TN	1671	HO2S Low Signal - Bank 2 Sensor 2
22-23	-	-	Not Used
24	BK	2760	Low Reference
25-32	-	-	Not Used
33	GY	2365	Low Reference
34	TN	472	IAT Sensor Signal
35	GY	597	5-Volt Reference
36-44	-	-	Not Used
45	YE	400	Signal High - Front
46-48	-	-	Not Used
49	BK	2759	Low Reference
50	-	-	Not Used
51	D-GN/WH	459	A/C Compressor Clutch Relay Control
52-56	-	-	Not Used