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Home >> Cadillac >> 2006 >> STS V >> Repair and Diagnosis (Single Page) >> Quick Lookups >> Wiring Diagrams >> OEM Connector End Views - Splice Pack, Power And Grounding, HVAC, Hydraulic Brake, Rear Axle, Tire Pressure Monitoring, Theft Deterrent, Horn, Steering Assist, Cruise Control, Entertainment, Engine Controls >> Engine Control Module Connector End Views >> Engine Control Module (ECM) Connector End View C3
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Engine Control Module (ECM) Connector End View C3

Fig 1: ECM C3 Connector
GM1650395Courtesy of GENERAL MOTORS CORP.
Engine Control Module Connector End Views

Connector Part Information 
  • OEM: 34566-3303
  • Service: 88988372
  • Description: 73-Way F (GY)
Terminal Part Information 
  • Pins: 73
  • Terminal/Tray: 7116-4152-02/9
  • Core/Insulation Crimp: 2/5
  • Release Tool/Test Probe: 12094430/J-35616-35 (VT)
  • Pins: 3, 4, 5, 6, 7, 14, 15, 16, 18, 21, 22, 23, 29, 33, 34, 35, 37, 38, 39, 46, 50, 53, 55, 56, 57, 58, 59
  • Terminal/Tray: 33467-0005/23
  • Core/Insulation Crimp: J/J
  • Release Tool/Test Probe: J-38125-213/J-35616-64B (L-BU)
  • Pins: 48, 49
  • Terminal/Tray: 33467-0003/23
  • Core/Insulation Crimp: H/H
  • Release Tool/Test Probe: J-38125-213/J-35616-64B (L-BU)
Engine Control Module (ECM) C3

Pin Wire Color Circuit No. Function
1-2 - - Not Used
3 TN/WH 3211 HO2S Low Reference (Bank 2 Sensor 1)
4 PU/WH 3210 HO2S Reference Voltage (Bank 2 Sensor 1)
5 PU 3220 HO2S High Signal (Bank 2 Sensor 2)
6 TN 3221 HO2S Low Signal (Bank 2 Sensor 2)
7 OG 225 Generator Turn On Signal
8-13 - - Not Used
14 L-BU 7126 Super Charger Vacuum Bypass Valve Control
15 L-GN 3212 HO2S Heater Low Control (Bank 2 Sensor 1)
16 PK 2014 Coolant Pump Relay Control
17 - - Not Used
18 BN 1174 Oil Level Switch Signal
19-20 - - Not Used
21 BK/WH 2751 Low Reference
22 OG/BK 6014 BARO Sensor Low Reference
23 OG/BK 469 Low Reference
24-28 - - Not Used
29 GY 23 Generator Field Duty Cycle Signal
30-32 - - Not Used
33 TN 2501 High Speed GMLAN Serial Data Bus -
34 YE/BK 6120 IAT2 Low Reference
35 TN 2761 Low Reference
36 - - Not Used
37 GY 2700 5-Volt Reference
38 WH/BK 2932 5-Volt Reference
39 GY 2704 5-Volt Reference
40-45 - - Not Used
46 OG/BK 1786 Park/Neutral Signal
47 - - Not Used
48 PU 428 EVAP Canister Purge Solenoid Control
49 D-GN 335 Low Speed Cooling Fan Relay Control
50 OG/BK 3223 HO2S Heater Low Control (Bank 2 Sensor 2)
51-52 - - Not Used
53 TN-BK 2500 High Speed GMLAN Serial Data Bus +
54 - - Not Used
55 YE 410 ECT Sensor Signal
56 L-BU 6118 IAT2 Signal
57 OG/BK 380 A/C Refrigerant Pressure Sensor Signal
58 GY-BK 433 BARO Sensor Signal
59 L-GN 432 MAP Sensor Signal
60-72 - - Not Used
73 BK/WH 1551 Ground


Fig 1: ECM C3 Connector
GM1420559Courtesy of GENERAL MOTORS CORP.
Engine Control Module Connector End Views

Connector Part Information 
  • OEM: 15418484
  • Service: 88953347
  • Description: 56-Way F 105-B (GY)
Terminal Part Information 
  • Pins: 1, 2, 3, 12, 13, 16, 18, 19, 20, 21, 22, 23, 24, 25, 37, 38, 40, 41, 42, 43, 44, 45, 46, 48, 49, 51
  • Terminal/Tray: 15359541/4
  • Core/Insulation Crimp: M/M
  • Release Tool/Test Probe: 15381651-2/J-35616-64B (L-BU)
Engine Control Module (ECM) C3

Pin Wire Color Circuit No. Function
1 PU/WH 3110 Heated Oxygen Sensor High Signal Bank 1 Sensor (1)
2 TN/WH 3111 Heated Oxygen Sensor Low Signal Bank 1 Sensor (1)
3 PU/WH 5281 Heated Oxygen Sensor Pump Current Bank 2 Sensor (1)
4-11 - - Not Used
12 D-BU 1936 Primary Fuel Level Sensor Signal
13 GY/WH 3122 Heated Oxygen Sensor Heater Low Control Bank 1 Sensor (2)
14-15 - - Not Used
16 OG/WH 3223 Heated Oxygen Sensor Heater Low Control Bank 2 Sensor (2)
17 - - Not Used
18 OG/BK 1786 Transmission Park/Neutral Signal (1)
19 TN/WH 3121 Heated Oxygen Sensor Low Signal Bank 1 Sensor (2)
20 PU 3220 Heated Oxygen Sensor High Signal Bank 2 Sensor (2)
21 TN 3221 Heated Oxygen Sensor Low Signal Bank 2 Sensor (2)
22 OG 5280 Heated Oxygen Sensor Input Pump Current Bank 2 Sensor (1)
23 BN 1174 Oil Level Switch Signal
24 L-BU 1937 Secondary Fuel Level Sensor Signal
25 TN/WH 331 Oil Pressure Sensor Signal
26-36 - - Not Used
37 TN 2759 Fuel Tank Pressure Sensor Low Reference
38 BK 2755 Oil Pressure Sensor Low Reference
39 - - Not Used
40 GY/WH 3113 Heated Oxygen Sensor Heater Low Control Bank 1 Sensor (1)
41 L-GN 3212 Heated Oxygen Sensor Heater Low Control Bank 2 Sensor (1)
42 GY 2709 5-Volt Reference (LH1/LH2)
43 PU 3120 Heated Oxygen Sensor High Signal Bank 1 Sensor (2)
44 D-GN 890 Fuel Tank Pressure Sensor Signal
45 PU/WH 3210 Heated Oxygen Sensor High Signal Bank 2 Sensor (1)
46 TN/WH 3211 Heated Oxygen Sensor Low Signal Bank 2 Sensor (1)
47 - - Not Used
48 WH 5279 Heated Oxygen Sensor Pump Current Bank 1 Sensor (1)
49 L-GN 5278 Heated Oxygen Sensor Input Pump Current Bank 1 Sensor (1)
50 - - Not Used
51 GY 2705 Oil Pressure Sensor 5-Volt Reference
52-56 - - Not Used
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