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Home >> Hummer >> 2008 >> H3 Base, Standard >> Repair and Diagnosis >> Electrical >> Component Locations >> Component Locations & Connector End Views >> Component Connector End Views >> Engine Control Module (ECM) X3
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Engine Control Module (ECM) X3

Fig 1: Engine Control Module (ECM) X3 Connector End View
GM1673472Courtesy of GENERAL MOTORS CORP.
Engine Control Module (ECM) X3

Pin Wire Circuit Function
1-2 - - Not Used
3 0.5 TN 1667 HO2S Low Signal - Bank 2 Sensor 1 (LH8)
4 0.5 PU 1666 HO2S High Signal - Bank 2 Sensor 1 (LH8)
5 0.5 PU 1670 HO2S High Signal - Bank 2 Sensor 2 (LH8)
6 0.5 TN 1671 HO2S Low Signal - Bank 2 Sensor 2 (LH8)
7 0.5 PU 5428 Generator Regulator Control
8 - - Not Used
9 0.5 BN 436 AIR Relay Control (K18)
10-11 - - Not Used
12 0.5 TN/BK 464 Delivered Torque Signal
13-14 - - Not Used
15 0.5 L-GN 3212 HO2S Heater Low Control - Bank 2 Sensor 1 (LH8)
16 - - Not Used
17 0.5 OG/BK 463 Requested Torque Signal
18-20 - - Not Used
21 0.5 BK 2751 Low Reference
22 - - Not Used
23 0.5 OG/BK 469 Low Reference
24-25 - - Not Used
26 0.5 D-BU/WH 6785 Low Reference (K18)
27 0.5 D-GN/WH 6294 Low Reference (MA5)
28 - - Not Used
29 0.5 GY 23 Generator Field Duty Cycle Signal
30-32 - - Not Used
33 0.5 TN 2501 High Speed GMLAN Serial Data Bus -
34 - - Not Used
35 0.5 BK 2761 Low Reference
36 - - Not Used
37 0.5 GY 2700 5-Volt Reference 1
38 - - Not Used
39 0.5 GY 2704 5-Volt Reference 1
40-41 - - Not Used
42 0.5 BN/WH 6789 5-Volt Reference (K18)
43 0.5 D-GN 6293 5-Volt Reference (MA5)
44-45 - - Not Used
46 0.5 D-GN 1433 PNP/Clutch Start Switch Signal (M30)
47 - - Not Used
48 0.5 D-GN/WH 428 EVAP Canister Purge Solenoid Control
49 - - Not Used
50 0.5 RD/WH 3223 HO2S Heater Low Control - Bank 2 Sensor 2 (LH8)
51-52 - - Not Used
53 0.5 TN/WH 2500 High Speed GMLAN Serial Data Bus +
54 - - Not Used
55 0.5 YE 410 ECT Sensor Signal
56 - - Not Used
57 0.5 RD/BK 380 A/C Refrigerant Pressure Sensor Signal
58 - - Not Used
59 0.5 L-GN 432 MAP Sensor Signal
60-61 - - Not Used
62 0.5 YE 6787 Air Injection Reaction Control Valve Control (K18)
63 0.5 D-BU 6303 CPP Sensor Signal (MA5)
64 - - Not Used
65 0.5 TN/BK 231 Oil Pressure Switch Signal (LLR)
66 0.5 PU/WH 821 VSS High Signal (MA5)
67 0.5 L-GN/BK 822 VSS Low Signal (MA5)
68-73 - - Not Used
Connector Part Information 
  • OEM: 34566-1243
  • Service: See Catalog
  • Description: 73-Way F MX123 34566 Series (GY)
Terminal Part Information 
  • Terminal/Tray: 33467-0005/23
  • Core/Insulation Crimp: J/J
  • Release Tool/Test Probe: J-38125-213/J-35616-64B (L-BU)