Engine Control Module (ECM) X3 (LGH)

2011 Chevrolet Chevy Express G3500, Van Cargo Extended, 6.6 LSECTION Engine Control Module (ECM) X3 (LGH)
Fig 1: Connector End View (LF1) Engine Control Module (ECM) X3 (LGH)
GM1968294Courtesy of GENERAL MOTORS CORP.
Engine Control Module (ECM) X3 (LGH)

Pin Wire Circuit Function
1 - - Not Available
2 0.5 BU/YE 6861 Water In Fuel Sensor Signal
3 - - Not Available
4 0.5 TN/WH 331 Oil Pressure Sensor Signal
5 - - Not Available
6 0.5 PU/WH 7584 Exhaust Gas Recirculation Temperature Sensor 1 Supply Voltage
7 0.5 D-BU 7583 Exhaust Gas Recirculation Temperature Sensor 2 Supply Voltage
8 - - Not Available
9 0.5 BN/WH 5763 Exhaust Gas Recirculation Valve Sensor Signal
10 0.5 YE 5947 Variable Nozzle Turbo Position Sensor Signal
11 0.5 YE 1578 Fuel Temperature Signal
12 0.5 BN 3681 Charge Air Cooler Outlet Temperature Sensor Signal
13 0.5 TN 3680 Charge Air Cooler Outlet Temperature Sensor Return
14 0.5 TN 2917 5 Volt Reference
15 - - Not Available
16 0.5 GY 2704 5 Volt Reference
17 0.5 D-BU 6863 Low Reference
18 0.5 D-BU 5277 Exhaust Gas Temperature Sensor 1 Signal
19 0.5 D-GN 485 Throttle Position Sensor Signal 1
20 0.5 YE 2918 Fuel Rail Pressure Sensor Signal
21 0.5 L-GN 432 Manifold Absolute Pressure Sensor Signal
22-23 - - Not Available
24 0.5 YE 410 Engine Coolant Temperature Sensor Signal
25-26 - - Not Available
27 0.5 BN/GY 7072 Sensor Fuel Temperature 1 Signal
28 0.5 D-GN 3683 Charge Air Cooler Inlet Temperature Sensor Signal
29 0.5 TN/BK 3682 Charge Air Cooler Inlet Temperature Sensor Return
30 0.5 GY 2705 5 Volt Reference
31 0.5 D-BU 6259 5 Volt Reference
32 0.5 GY 2701 5 Volt Reference
33-35 - - Not Available
36 0.5 OG/BK 2919 Low Reference
37 0.5 OG/BK 469 Low Reference
38-39 - - Not Available
40 0.5 TN 2761 Low Reference
41-43 - - Not Available
44 0.5 GY/BK 5765 Fuel Filter Pressure Switch Signal
45 - - Not Available
46 0.5 BN/WH 7073 Sensor Fuel Temperature 1 Return
47 - - Not Available
48 0.5 BN 6062 Low Reference
49 0.8 GY/WH 4908 Direct Fuel Injector (DFI) High Voltage Supply Cylinder 8
50 0.8 D-BU/WH 4902 Direct Fuel Injector (DFI) High Voltage Supply Cylinder 2
51 0.8 D-BU 4802 Direct Fuel Injector (DFI) High Voltage Control Cylinder 2
52 0.8 L-BU 4805 Direct Fuel Injector (DFI) High Voltage Control Cylinder 5
53 - - Not Available
54 0.5 L-GN/BK 5746 Exhaust Gas Recirculation Valve Motor Low Signal
55 0.5 OG/BK 5764 Exhaust Gas Recirculation Valve Motor High Signal
56 0.8 BN 582 Throttle Actuator Control Close
57 0.8 YE 581 Throttle Actuator Control Open
58-59 - - Not Available
60 0.5 GY/BK 6272 Low Reference
61 0.5 WH/BK 6271 CKP Sensor Signal
62-64 - - Not Available
65 0.5 D-BU/WH 6265 CMP Sensor Signal
66 0.5 BN 6266 Low Reference
67 0.5 BN 6274 Low Reference
68 0.5 WH 6275 Low Reference
69 0.8 D-GN/WH 4903 Direct Fuel Injector (DFI) High Voltage Supply Cylinder 3
70 0.8 L-GN/WH 4905 Direct Fuel Injector (DFI) High Voltage Supply Cylinder 5
71 0.8 D-GN 4803 Direct Fuel Injector (DFI) High Voltage Control Cylinder 3
72 0.8 GY 4808 Direct Fuel Injector (DFI) High Voltage Control Cylinder 8
73 3 BK/WH 451 Ground
Connector Part Information
  • Harness Type: Engine Chassis
  • OEM Connector: 12603597
  • Service Connector: 13574948
  • Description: 73-Way F MX123 34566 Series (GY)
Terminal Part Information
  • Pins: 2, 4, 6-7, 9-14, 16-21, 24, 27-32, 36-37, 40, 44, 46, 48-52, 54-57, 60-61, 65-72
  • Terminated Lead: 13575575
  • Release Tool: J-38125-213
  • Diagnostic Test Probe: J-35616-64B (L-BU)
  • Terminal/Tray: 33467-0005/23
  • Core/Insulation Crimp: Pins: 2, 4, 6-7, 9-14, 16-21, 24, 27-32, 36-37, 40, 44, 46, 48, 54-55, 60-61, 65-68 - J/J
  • Core/Insulation Crimp: Pins: 49-52, 56-57, 69-72 - K/K
  • Pin 73
  • Terminated Lead: Pending
  • Release Tool: J-38125-11A
  • Diagnostic Test Probe: J-35616-35 (VT)
  • Terminal/Tray: 7116-4152-02/9
  • Core/Insulation Crimp: A/5
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.