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Home >> Chevrolet >> 2006 >> HHR LS, Standard >> Repair and Diagnosis >> Electrical >> Body Electrical >> OEM Connector End Views >> Engine Control Module (ECM) Connector End Views (2.4L) >> Engine Control Module (ECM) Connector End View C2
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Engine Control Module (ECM) Connector End View C2

Fig 1: ECM C2 Connector
GM1335545Courtesy of GENERAL MOTORS CORP.
Engine Control Module (ECM) Connector End Views

Connector Part Information 
  • OEM: 34566-2503
  • Service: 88988360
  • Description: 73-Way F Micro-Pack 64 Series (BU)
Terminal Part Information 
  • Pins:
  • Terminal:
  • Core/Insulation Crimp:
  • Release Tool/Test Probe:
Engine Control Module (ECM) C2

Pin Wire Color Circuit No. Function
1 PU 2121 Ignition Control (1)
2 TN/WH 3111 Heated Oxygen Sensor Low Signal Bank 1 Sensor 1
3 PU/WH 3110 Heated Oxygen Sensor High Signal Bank 1 Sensor 1
4 PU/WH 1668 Heated Oxygen Sensor High Signal Bank 1 Sensor 2
5 TN/WH 1669 Heated Oxygen Sensor Low Signal Bank 1 Sensor 2
6-7 - - Not Used
8 D-BU 496 Knock Sensor Signal (1)
9 GY 1716 Knock Sensor Low Reference (1)
10 - - Not Used
11 YE 581 Throttle Actuator Control Open
12 BN 582 Throttle Actuator Control Close
13 PK/BK 5290 Engine Main Relay Fused Control (1)
14 PK/BK 6395 Cam Phaser #2 Control
15-16 - - Not Used
17 L-BU 2123 Ignition Control (3)
18-19 - - Not Used
20 GY 5296 Camshaft Position Exhaust Sensor Low Reference (1)
21-22 - - Not Used
23 TN 5301 Camshaft Position Intake Sensor Low Reference (1)
24-26 - - Not Used
27 PU 574 Crankshaft Position Sensor Low Reference (1)
28 - - Not Used
29 TN 2752 Throttle Position Sensor Low Reference
30 L-GN 5282 Camshaft Phaser Exhaust Solenoid (1)
31 - - Not Used
32 L-GN/BK 1745 Fuel Injector Control (2)
33 D-GN/WH 2124 Ignition Control (4)
34 - - Not Used
35 BN 2129 Ignition Control Low Reference Bank 1
36 YE/BK 5297 Camshaft Position Exhaust Sensor Supply Voltage (1)
37-38 - - Not Used
39 D-BU 5300 Camshaft Position Intake Sensor Supply Voltage (1)
40-41 - - Not Used
42 TN 2760 Intake Air Temperature Sensor Low Reference
43 L-GN 2867 Crankshaft Position Sensor Supply Voltage
44 GY 2701 Throttle Position Sensor 5-Volt Reference
45 - - Not Used
46 PU 5284 Camshaft Phaser Intake Solenoid (1)
47 - - Not Used
48 PK/BK 1746 Fuel Injector Control (3)
49 - - Not Used
50 WH/BK 6396 Cam Phaser #3 Control
51-52 - - Not Used
53 OG/WH 2122 Ignition Control (2)
54-55 - - Not Used
56 D-GN 5273 Camshaft Position Exhaust Sensor (1)
57-58 - - Not Used
59 OG 5275 Camshaft Position Intake Sensor (1)
60-61 - - Not Used
62 TN 472 Intake Air Temperature Sensor Signal
63 YE 573 Crankshaft Position Sensor Signal (1)
64 D-GN 485 Throttle Position Sensor Signal (1)
65 - - Not Used
66 PU 486 Throttle Position Sensor Signal (2)
67 YE 492 Mass Air Flow Sensor Signal
68 GY/WH 3113 Heated Oxygen Sensor Heater Low Control Bank 1 Sensor 1
69 GY/WH 3122 Heated Oxygen Sensor Heater Low Control Bank 1 Sensor 2
70 - - Not Used
71 L-BU/BK 844 Fuel Injector Control (4)
72 TN 1744 Fuel Injector Control (1)
73 BK/WH 451 Signal Ground