Engine Control Module (ECM) Connector End Views

WARNING: This page is about a different car, the 2006 Saturn Ion 3. 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		34040-1103 56-Way F Micro-Pack 64 Series Sealed (BU)
Pin	Wire Color	Circuit No.	Function
1	-	-	Not Used
2	PU	420	TCC Switch/Cruise Control Release Signal
3-5	-	-	Not Used
6	BN/WH	379	CPP Switch Signal
7	L-BU	20	Stop Lamp Supply Voltage
8	-	-	Not Used
9	BK	2759	Low Reference
10-11	-	-	Not Used
12	BN/WH	419	MIL Control
13	D-GN/WH	465	Fuel Pump Relay Control
14	-	-	Not Used
15	PU	1807	Class 2 Serial Data
16	PU	1807	Class 2 Serial Data
17	-	-	Not Used
18	BN	4	Accessory Voltage
19	YE	1139	Ignition 1 Voltage
20	OG	480	Battery Positive Voltage
21-28	-	-	Not Used
29	GY	1884	Cruise Control Set/Coast and Resume/Accelerate Signal
30-32	-	-	Not Used
33	WH/BK	1164	5-Volt Reference B
34	GY	705	5-Volt Reference A
35	PU	1272	5-Volt Reference A
36	BN	1271	Low Reference
37	TN	1274	Low Reference
38-39	-	-	Not Used
40	BN	5069	Powertrain Relay Control
41-43	-	-	Not Used
44	PU	1589	Fuel Level Sensor Signal
45-46	-	-	Not Used
47	D-BU	1161	APP Sensor 1 Signal
48	D-GN	890	Fuel Tank Pressure Sensor Signal
49	L-BU	1162	APP Sensor 2 Signal
50-52	-	-	Not Used
53	D-GN/WH	459	A/C Compressor Clutch Relay Control
54	D-BU	473	High Speed Cooling Fan Relay Control
55	WH	1310	EVAP Canister Vent Solenoid Control
56	YE	447	Starter Relay Coil Control

Engine Control Module (ECM) C2

Courtesy of GENERAL MOTORS CORP.
Connector Part Information		34566-2503 73-Way F Micro-Pack 64 Series Sealed (BK)
Pin	Wire Color	Circuit No.	Function
1	PU	2121	IC 1 Control
2	TN/WH	3111	HO2S Low Signal (Sensor 1)
3	PU/WH	3110	HO2S High Signal (Sensor 1)
4	PU/WH	1668	HO2S High Signal (Sensor 2)
5	TN/WH	1669	HO2S Low Signal (Sensor 2)
6-7	-	-	Not Used
8	D-BU	496	Knock Sensor Signal
9	GY	1716	Low Reference
10	-	-	Not Used
11	YE	581	TAC Motor Control 1
12	BN	582	TAC Motor Control 2
13	PK/BK	5290	Ignition 1 Voltage
14	PK/BK	6395	CMP Actuator Solenoid Control Intake
15-16	-	-	Not Used
17	L-BU	2123	IC 3 Control
18-19	-	-	Not Used
20	GY	5296	Low Reference
21-22	-	-	Not Used
23	TN	5301	Low Reference
24-26	-	-	Not Used
27	PU	574	Low Reference
28	-	-	Not Used
29	BK	2752	Low Reference
30	L-GN	5282	Low Reference
31	-	-	Not Used
32	L-GN	1745	Fuel Injector 2 Control
33	D-GN/WH	2124	IC 4 Control
34	-	-	Not Used
35	BN	2129	Low Reference
36	YE/BK	5297	5-Volt Reference
37-38	-	-	Not Used
39	D-BU	5300	5-Volt Reference
40-41	-	-	Not Used
42	BK	2760	Low Reference
43	L-GN	2867	5-Volt Reference
44	GY	2701	5-Volt Reference B
45	-	-	Not Used
46	PU	5284	Low Reference
47	-	-	Not Used
48	PK/BK	1746	Fuel Injector 3 Control
49	-	-	Not Used
50	WH/BK	6396	CMP Actuator Solenoid Control Exhaust
51-52	-	-	Not Used
53	RD/WH	2122	IC 2 Control
54-55	-	-	Not Used
56	D-GN	5273	CMP Sensor Signal
57-58	-	-	Not Used
59	OG	5275	CMP Sensor Signal
60-61	-	-	Not Used
62	TN	472	IAT Sensor Signal
63	YE	573	CKP Sensor Signal
64	D-GN	485	TP Sensor 1 Signal
65	-	-	Not Used
66	PU	486	TP Sensor 2 Signal
67	YE	492	MAF Sensor Signal
68	BK/WH	3113	HO2S Heater Low Control (Sensor 1)
69	BK/WH	3122	HO2S Heater Low Control (Sensor 2)
70	-	-	Not Used
71	L-BU/BK	844	Fuel Injector 4 Control
72	BK	1744	Fuel Injector 1 Control
73	BK/WH	451	Ground

Engine Control Module (ECM) C3

Courtesy of GENERAL MOTORS CORP.
Connector Part Information		34566-2603 73-Way F Micro-Pack 64 Series Sealed (GY)
Pin	Wire Color	Circuit No.	Function
1-6	-	-	Not Used
7	RD	225	Generator Turn On Signal
8-20	-	-	Not Used
21	BK	2751	Low Reference
22	-	-	Not Used
23	OG/BK	469	Low Reference
24-27	-	-	Not Used
28	BK/WH	1704	Low Reference
29	GY	23	Generator Field Duty Cycle Signal
30-32	-	-	Not Used
33	TN	2501	High Speed GMLAN Serial Data Bus -
34	-	-	Not Used
35	BK	2761	Low Reference
36	-	-	Not Used
37	GY	2700	5-Volt Reference B
38	-	-	Not Used
39	GY	2704	5-Volt Reference A
40-43	-	-	Not Used
44	L-BU/BK	1688	5-Volt Reference B
45-46	-	-	Not Used
47	D-GN	1433	PNP/Clutch Start Switch Signal
48	D-GN/WH	428	EVAP Canister Purge Solenoid Control
49	D-GN	335	Low Speed Cooling Fan Relay Control
50-52	-	-	Not Used
53	TN/WH	2500	High Speed GMLAN Serial Data Bus +
54	-	-	Not Used
55	YE	410	ECT Sensor Signal
56	-	-	Not Used
57	RD/BK	380	A/C Refrigerant Pressure Sensor Signal
58	-	-	Not Used
59	L-GN	432	MAP Sensor Signal
60-64	-	-	Not Used
65	TN/BK	231	Oil Pressure Sensor Signal
66	YE	400	VSS Signal High (M86)
67	PU	401	VSS Signal Low (M86)
68-73	-	-	Not Used