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Home >> Saturn >> 2007 >> Relay 3.9 1 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls And Fuel - Introduction (2 Of 2) >> Component Locator >> Engine Control Module Connector End Views >> Engine Control Module (ECM) C3
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Engine Control Module (ECM) C3

Fig 1: Engine Control Module (ECM) C3 Connector End Views
GM1335545Courtesy of GENERAL MOTORS CORP.
Engine Control Module (ECM) C3 Connector Parts Information

Connector Part Information 
  • OEM: 34566-0203
  • Service: See Catalog
  • Description: 73-Way F MX123 Series Sealed (GY)
Terminal Part Information 
  • Pins: 7, 12, 17-18, 21, 23, 29, 32, 35, 37, 39, 46, 48-49, 55, 57, 59, 64, 66
  • Terminal/Tray: 33467-0003/23
  • Core/Insulation Crimp: H/H
  • Release Tool/Test Probe: J-38125-213/J-35616-64A (L-BU)
  • Pins: 33, 53
  • Terminal/Tray: 33467-0005/23
  • Core/Insulation Crimp: J/J
  • Release Tool/Test Probe: J-38125-213/J-35616-64A (L-BU)
Engine Control Module (ECM) C3 Connector Terminal Identification

Pin Wire Color Circuit No. Function
1-6 - - Not Used
7 OG 225 Generator Turn On Signal
8-11 - - Not Used
12 TN/BK 464 Delivered Torque Signal
13-16 - - Not Used
17 OG/BK 463 Requested Torque Signal
18 BN 1174 Oil Level Switch Signal
19-20 - - Not Used
21 BK/WH 2751 Low Reference
22 - - Not Used
23 OG/BK 469 Low Reference
24-28 - - Not Used
29 GY 23 Generator Field Duty Cycle Signal
30-31 - - Not Used
32 OG 6392 Variable Tuning Control
33 TN 2501 High Speed GMLAN Serial Data Bus (-)
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
40-45 - - Not Used
46 D-GN 6307 Park/Neutral Signal
47 - - Not Used
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 Bus (+)
54 - - Not Used
55 YE 410 ECT Sensor Signal
56 - - Not Used
57 OG/BK 380 A/C Refrigerant Pressure Sensor Signal
58 - - Not Used
59 L-GN 432 MAP Sensor Signal
60-63 - - Not Used
64 YE/BK 6806 Variable Tuning Position Sensor Signal
65 - - Not Used
66 BN/WH 6354 Output Speed High (Replicated TOSS) Input Signal
67-73 - - Not Used