Engine Control Module (ECM) X3

WARNING: This page is about a different car, the 2008 Cadillac DTS. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Engine Control Module (ECM) X3 Connector End View

Courtesy of GENERAL MOTORS CORP.

Pin	Wire	Circuit	Function
1-2	-	-	Not Used
3	0.5 TN/WH	3211	HO2S Low Reference Bank 1 Sensor 1
4	0.5 PU/WH	3210	HO2S Reference Voltage Bank 1 Sensor 1
5-6	-	-	Not Used
7	0.5 OG	225	Generator Turn On Signal
8	0.5 L-GN	1652	Reverse Lockout Solenoid Control
9	0.5 WH/BK	436	AIR Pump Relay Control
10-14	-	-	Not Used
15	0.8 L-GN/WH	3112	HO2S Heater Low Control Bank 1 Sensor 1
16-20	-	-	Not Used
21	0.5 L-BU	5514	Low Reference
22	-	-	Not Used
23	0.5 OG/BK	469	Low Reference
24-25	-	-	Not Used
26	0.5 WH/GY	6786	Low Reference
27-28	-	-	Not Used
29	0.5 GY	23	Generator Field Duty Cycle Signal
30-32	-	-	Not Used
33	0.35 TN	2501	High Speed GMLAN Serial Data Bus -
34	-	-	Not Used
35	0.35 PK	2761	Low Reference
36	-	-	Not Used
37	0.5 GY/BK	2700	5-Volt Reference 1
38	-	-	Not Used
39	0.5 GY/WH	2704	5-Volt Reference 1
40-41	-	-	Not Used
42	0.5 BN/WH	6790	5-Volt Reference 2
43-45	-	-	Not Used
46	0.5 GY/OG	1786	Park/Neutral Signal
47	-	-	Not Used
48	0.5 D-GN/WH	428	EVAP Canister Purge Solenoid Control
49	0.5 D-GN	335	Low Speed Cooling Fan Relay Control
50-52	-	-	Not Used
53	0.35 TN/BK	2500	High Speed GMLAN Serial Data Bus +
54	-	-	Not Used
55	0.5 YE	410	ECT Sensor Signal
56	-	-	Not Used
57	0.5 OG/WH	380	A/C Refrigerant Pressure Sensor Signal
58	-	-	Not Used
59	0.5 L-GN/BK	432	MAP Sensor Signal
60-61	-	-	Not Used
62	0.5 YE/GY	6788	Air Injection Position Signal
63-64	-	-	Not Used
65	0.5 YE/D-GN	231	Oil Pressure Switch Signal
66-73	-	-	Not Used

Connector Part Information

OEM: 34566-3103
Service: 88988612
Description: 73-Way F (GY)

Terminal Part Information

Terminal/Tray: 33467-0005/23
Core/Insulation Crimp: Pins 3, 4, 7-9, 18, 21, 23, 26, 29, 33, 35, 37, 39, 42, 46, 48, 49, 53, 55, 57, 59, 62, 65 - J/J
Core/Insulation Crimp: Pins 15 - K/K
Release Tool/Test Probe: J-38125-213/J-35616-64B (L-BU)