LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Cadillac >> 2012 >> CTS Base, 2D Coupe, AWD >> Repair and Diagnosis >> Electrical >> Wiring Diagrams >> Wiring Systems And Power Management - Component Connector End Views - ECM X3 (LSA) To Park Lamp Relay (T90) >> Component Connector End Views >> Engine Control Module (ECM) X3 (LSA)
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Engine Control Module (ECM) X3 (LSA)

GM1590596Courtesy of
Connector Part Information
  • Harness Type: Engine
  • OEM Connector: 34566-0203
  • Service Connector: 88988372
  • Description: 73-Way F MX123 34566 Series (BK with GY Terminal Position Assurance Lock)
Terminal Part Information
  • Pins: 3-8, 13, 15, 16, 18, 21, 27, 29, 33, 34, 37, 43, 46, 48-50, 53, 57, 63
  • Terminated Lead: 13575575
  • Release Tool: J-38125-213
  • Diagnostic Test Probe: J-35616-64B (L-BU)
  • Terminal/Tray: 33467-0005/23
  • Core/Insulation Crimp: J/J
  • Pins: 14, 45, 66, 67
  • Terminated Lead: 13575811
  • Release Tool: J-38125-213
  • Diagnostic Test Probe: J-35616-64B (L-BU)
  • Terminal/Tray: 33467-0003/23
  • Core/Insulation Crimp: H/H
  • Pins: 22, 23, 35, 36, 38, 39, 55, 56, 58, 59, 65
  • Terminated Lead: 13575575
  • Release Tool: J-38125-213
  • Diagnostic Test Probe: J-35616-64B (L-BU)
  • Terminal/Tray: 33467-0005/23
  • Core/Insulation Crimp: K/K
  • Pins: 73
  • Terminated Lead: Service by Harness - See Part Catalog
  • Release Tool: J-38125-11A
  • Diagnostic Test Probe: J-35616-35 (VT)
  • Terminal/Tray: 7116-4152-02/9
  • Core/Insulation Crimp: A/5
Engine Control Module (ECM) X3 (LSA)

Pin Wire Circuit Function
1-2 - - Not Used
3 0.5 TN 1667 HO2S Low Signal - Bank 2 Sensor 1
4 0.5 PU 1666 HO2S High Signal - Bank 2 Sensor 1
5 0.5 PU 1670 HO2S High Signal - Bank 2 Sensor 2
6 0.5 TN 1671 HO2S Low Signal - Bank 2 Sensor 2
7 0.5 OG 225 Generator Turn On Signal
8 0.5 L-GN 1652 Reverse Lockout Solenoid Signal (MG9)
9-12 - - Not Used
13 0.5 GY 587 Skip Shift Signal (MG9)
14 0.35 L-BU 7126 Super Charger Vacuum Bypass Valve Control
15 0.5 L-GN 3212 HO2S Heater Low Control - Bank 2 Sensor 1
16 0.5 PK 2014 Charge Air Cooler Coolant Pump Control
17 - - Not Used
18 0.8 BN 1174 Oil Level Switch Signal
19-20 - - Not Used
21 0.5 TN 5514 A/C Refrigerant Pressure Sensor Low Reference
22 0.8 OG/BK 6014 Barometric Pressure Sensor Low Reference
23 0.8 OG/BK 469 Manifold Absolute Pressure Sensor Low Reference
24-26 - - Not Used
27 0.5 OG/D-GN 7360 Manual Transmission Clutch Position Sensor Return (MG9)
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 0.5 TN 470 Sensor Low Reference
35 0.8 TN 2761 Coolant Temperature Sensor Low Reference
36 0.8 YE/BK 6120 Manifold Air Temperature Sensor Low Reference
37 0.5 GY 2700 A/C Pressure Sensor 5 Volt Reference
38 0.8 WH/BK 2932 Barometric Pressure Sensor (5) Volt Reference
39 0.8 GY 2704 Manifold Absolute Pressure Sensor 5 Volt Reference
40-42 - - Not Used
43 0.5 D-BU/YE 7361 Manual Transmission Clutch Position Sensor Supply (MG9)
44 - - Not Used
45 0.35 L-GN 5007 Backup Lamp Switch Signal (MG9)
46 0.5 OG/BK 1786 Ignition Lock Cylinder Control Actuator Signal (MYD)
47 - - Not Used
48 0.5 D-GN/WH 428 EVAP Canister Purge Solenoid Control
49 0.5 D-GN 335 Low Speed Cooling Fan Relay Control
50 0.5 OG/WH 3223 HO2S Heater Low Control - Bank 2 Sensor 2
51-52 - - Not Used
53 0.5 TN/BK 2500 High Speed GMLAN Serial Data Bus+
54 - - Not Used
55 0.8 YE 410 Engine Coolant Temperature Sensor Signal
56 0.8 L-BU 6118 Manifold Air Temperature Sensor Signal
57 0.5 OG/BK 380 A/C Refrigerant Pressure Sensor Signal
58 0.8 GY/BK 433 Barometric Pressure Sensor Signal
59 0.8 L-GN 432 Manifold Absolute Pressure Sensor Signal
60-62 - - Not Used
63 0.5 L-GN 6338 Manual Transmission Clutch Position Sensor Signal Position (MG9)
64-65 - - Not Used
66 0.35 YE 400 Vehicle Speed Sensor Signal
67 0.35 PU 401 Vehicle Speed Sensor Low Reference
68-72 - - Not Used
73 3.0 BK 1550 Ground
scientia non olet · About LEMON Manuals