Engine Control Module (ECM) Connectors

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2005 Isuzu Ascender, 2005 GMC Envoy XUV, 2005 GMC Envoy XL, 2005 GMC Envoy, and 2005 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.

Engine Control Module (ECM) C1

Courtesy of GENERAL MOTORS CORP.
Connector Part Information		15491996 56-Way F Micro-Pack 64 Series (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 (K34)
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 (K34)
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 (K34)
33	GY/BK	87	Cruise Control Resume/Accel Switch Signal (K34)
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 150 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	OG	5494	Cylinder Shutoff Solenoid Control 4 (DOD)
18	GY	5493	Cylinder Shutoff Solenoid Control 3 (DOD)
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	-	-	Not Used
33	D-BU	5491	Cylinder Shutoff Solenoid Control 1 (DOD)
34	L-GN	5492	Cylinder Shutoff Solenoid Control 2 (DOD)
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 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
4-5	-	-	Not Used
6	D-BU	1809	Brake Booster Vacuum Sensor Signal (DOD)
7-10	-	-	Not Used
11	YE	492	MAF Sensor Signal
12-14	-	-	Not Used
15	GY	416	5-Volt Reference (DOD)
16-17	-	-	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
25-28	-	-	Not Used
29	GY/BK	1694	4WD Low Signal
30-32	-	-	Not Used
33	GY	2365	Low Reference
34	TN	472	IAT Sensor Signal
35	GY	597	5-Volt Reference
36	BK	452	Low Reference (DOD)
37	-	-	Not Used
38	TN/BK	464	Delivered Torque Signal
39-44	-	-	Not Used
45	YE	400	Signal High - Front
46	-	-	Not Used
47	OG/BK	463	Requested Torque Signal
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