Engine Control Module (ECM) Connector End View 1

Fig 1: Connector End View

Courtesy of GENERAL MOTORS CORP.

Engine Control Module Connector End Views

Connector Part Information  OEM: 34566-2603 Service: 88988372 Description: 73-Way F Micro-Pack 64 Series (BK)

Terminal Part Information  Pins: 7, 21, 23, 28, 29, 33, 35, 37, 39, 44, 47-49, 53, 55, 57, 59, 65-67 Terminal/Tray: See Terminal Repair Kit Core/Insulation Crimp: See Terminal Repair Kit Release Tool/Test Probe: See Terminal Repair Kit

Connector Terminal Identification

Pin	Wire Color	Circuit No.	Function
1-6	-	-	Not Used
7	OG	225	Generator Turn On Signal
8-20	-	-	Not Used
21	BK/WH	2751	Low Reference
22	-	-	Not Used
23	OG/BK	469	Low Reference
24-27	-	-	Not Used
28	TN/WH	1704	Low Reference
29	GY	23	Generator Field Duty Cycle Signal
30-32	-	-	Not Used
33	TN	2501	High Speed GMLAN Serial Data (-) (1)
34	-	-	Not Used
35	TN	2761	Low Reference
36	-	-	Not Used
37	GY	2700	5-Volt Reference
38	-	-	Not Used
39	GY	2704	5-Volt Reference
40-43	-	-	Not Used
44	L-BU/BK	1688	5-Volt Reference
45-46	-	-	Not Used
47	D-GN	1433	PNP/Clutch Start Switch Signal (M86)
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/BK	2500	High Speed GMLAN Serial Data (+) (1)
54	-	-	Not Used
55	YE	410	Engine Coolant Temperature Sensor Signal
56	-	-	Not Used
57	OG/BK	380	A/C Refrigerant Pressure Sensor Signal
58	-	-	Not Used
59	L-GN	432	Manifold Absolute Pressure Sensor Signal
60-64	-	-	Not Used
65	TN/BK	231	Oil Pressure Switch Signal
66	YE	400	Vehicle Speed Sensor Signal High (w/M86)
67	PU	401	Vehicle Speed Sensor Low (w/M86)
68-73	-	-	Not Used