Engine Control Module (ECM) X1 (HP2)

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Fig 1: Engine Control Module (ECM) X1 (HP2) Connector End View

Courtesy of GENERAL MOTORS CORP.

Pin	Wire Color	Circuit	Function
1-2	-	-	Not Used
3	0.5 PU	5531	Hood Switch Signal
4-6	-	-	Not Used
7	0.5 L-BU/WH	6311	Brake Pedal Switch Signal
8	0.5 PK/BK	109	Hood Ajar Switch Signal
9	0.35 TN/BK	6049	Low Reference
10-11	-	-	Not Used
12	0.35 BN/WH	419	Malfunction Indicator Lamp (MIL) Control
13	0.35 D-GN/WH	465	Fuel Pump Relay Control
14-17	-	-	Not Used
18	0.5 D-BU	5985	Serial Data Wake-Up Signal
19	0.5 PK	439	Ignition Voltage
20	0.5 RD/WH	440	Battery Positive Voltage
21-32	-	-	Not Used
33	0.35 WH/BK	1164	5-Volt Reference
34	0.35 GY	2709	5-Volt Reference
35	0.35 TN	1274	5-Volt Reference
36	0.35 BN	1271	Low Reference
37	0.35 PU	1272	Low Reference
38-39	-	-	Not Used
40	0.35 YE	5991	Powertrain Relay Coil Control
41	0.35 PU	5128	High Speed Cooling Fan Relay Control
42-43	-	-	Not Used
44	0.35 PU	1589	Fuel Level Sensor Signal
45-46	-	-	Not Used
47	0.35 D-BU	1161	Accelerator Pedal Position Sensor 1 Signal
48	0.35 D-GN	890	Fuel Tank Pressure Sensor Signal
49	0.35 L-BU	1162	Accelerator Pedal Position Sensor 2 Signal
50-53	-	-	Not Used
54	0.35 D-GN	335	Medium Speed Cooling Fan Relay Control
55	0.5 WH	1310	EVAP Canister Vent Solenoid Control
56	-	-	Not Used

Connector Part Information

OEM: 13510837
Service: 88988373
Description: 56-Way F MX123 Series (BK)

Terminal Part Information

Pins: 3-8, 18-20, 55
Terminal/Tray: 33467-0005/23
Core/Insulation Crimp: J/J
Release Tool/Test Probe: J-38125-213/J-35616-64B (L-BU)

Pins: 9-13, 33-54
Terminal/Tray: 33467-0003/23
Core/Insulation Crimp: H/H
Release Tool/Test Probe: J-38125-213/J-35616-64B (L-BU)