GM Service Manual Online
For 1990-2009 cars only
Figure 1:

Engine Harness Jumper to Engine POA Harness Diesel


Object Number: 1870628  Size: LF
(1)Battery - Right
(2)Fuse Holder - Underhood
(3)X127
(4)X108
(5)X107
(6)X123 (PTO)
(7)Fuse Block - Underhood
(8)X109
(9)Battery - Left (6A6/TP2)
(10)Engine Control Module (ECM)
(11)Transmission Control Module (TCM)
Figure 2:

Front of Engine Compartment (4.3L)


Object Number: 1888657  Size: LF
(1)Battery Current Sensor
(2)Mega Fuse
(3)A/C Low Pressure Switch (C67/CJ2)
(4)Fuse Block - Underhood
(5)Engine Control Module (ECM)
(6)A/C Refrigerant Pressure Sensor (C67/CJ2)
(7)Mass Airflow (MAF)/Intake Air Temperature (IAT) Sensor
(8)Battery - Right
Figure 3:

Front of the Engine (Gas - 4.3L)


Object Number: 1714191  Size: LF
(1)Throttle Body
(2)Manifold Absolute Pressure (MAP) Sensor
(3)Evaporative Emission (EVAP) Canister Purge Solenoid Valve
(4)Knock Sensor (KS) - 1
(5)Engine Block Heater
(6)Engine Coolant Temperature (ECT) Sensor
(7)Camshaft Position (CMP) Sensor
(8)Generator
Figure 4:

Auxiliary Battery Harness (TP2)


Object Number: 1934393  Size: LF
(1)Fuse Holder - Underhood
(2)Run Relay
(3)Auxiliary Battery Harness
(4)Auxiliary Battery Relay
(5)X122
Figure 5:

Top of Engine Diesel


Object Number: 1870624  Size: LF
(1)Turbocharger Vane Position Control Solenoid Valve
(2)Glow Plug Control Module (GPCM)
(3)Fuel Rail Temperature (FRT) Sensor
(4)Intake Air Temperature (IAT) Sensor 2 Connector
(5)X128
(6)A/C Refrigerant Pressure Sensor (C67/CJ2)
(7)Generator - Left (K76)
(8)A/C Compressor Clutch (C67/CJ2)
(9)Engine Coolant Temperature (ECT) Sensor 1
(10)Engine Coolant Temperature (ECT) Sensor 2
(11)Camshaft Position (CMP) Sensor
(12)X127
(13)Generator - Right
(14)Manifold Absolute Pressure (MAP) Sensor
(15)Intake Air Heater (IAH) Module
(16)Intake Air Temperature (IAT) Sensor 2
(17)Fuel Heater
(18)A/C Low Pressure Switch (C67/CJ2)
Figure 6:

Left Side of Engine (4.3L)


Object Number: 1887842  Size: LF
(1)Generator
(2)Throttle Body
(3)Transmission
(4)Park/Neutral Position (PNP) Switch
(5)Heated Oxygen Sensor (HO2S) Bank 1 Sensor 2
(6)Heated Oxygen Sensor (HO2S) Bank 1 Sensor 1
(7)Knock Sensor (KS) - 1
(8)Engine Coolant Temperature (ECT) Sensor
(9)A/C Compressor Clutch (C67/CJ2)
Figure 7:

Right Side of Engine (4.3L)


Object Number: 1887852  Size: LF
(1)Evaporative Emission (EVAP) Canister Purge Solenoid Valve
(2)Throttle Body
(3)Mass Air Flow (MAF) / Intake Air Temperature (IAT) Sensor
(4)X112
(5)G103
(6)Crankshaft Position (CKP) Sensor
(7)Knock Sensor (KS) - 2
(8)Starter
(9)Heated Oxygen Sensor (HO2S) Bank 2 Sensor 1
(10)Heated Oxygen Sensor (HO2S) Bank 2 Sensor 2
(11)Vehicle Speed Sensor (VSS)
Figure 8:

Right Side of the Engine (Gas -4.3L)


Object Number: 1714216  Size: LF
(1)Ignition Coil 8
(2)Ignition Coil 6
(3)Ignition Coil 4
(4)Manifold Absolute Pressure (MAP) Sensor
(5)Throttle Body
(6)Ignition Coil 2
(7)Knock Sensor (KS) - 2
(8)Crankshaft Position (CKP) Sensor
(9)Engine Oil Level Switch
(10)Starter
(11)Valve Lifter Oil Manifold (VLOM) Assembly
(12)Engine Oil Pressure Sensor
Figure 9:

Right Side of Engine (Diesel)


Object Number: 1870626  Size: LF
(1)Fuel Injector 7
(2)Fuel Injector 5
(3)Fuel Injector 3
(4)Exhaust Gas Recirculation (EGR) Valve
(5)Fuel Injector 1
(6)Mass Air Flow (MAF)/Intake Air Temperature (IAT) Sensor
(7)Intake Air Valve
(8)Crankshaft Position (CKP) Sensor
(9)Glow Plug 1
(10)G103
(11)G105
(12)Block Heater
(13)Glow Plug 3
(14)Glow Plug 5
(15)Water In Fuel Sensor
(16)Starter
(17)Glow Plug 7
Figure 10:

Right Rear of the Engine Compartment (Gas -4.3L)


Object Number: 1714221  Size: LF
(1)Battery - Right
(2)A/C Low Pressure Switch (C67/CJ2)
(3)A/C Compressor Clutch (C67/CJ2)
(4)A/C Refrigerant Pressure Sensor (C67/CJ2)
(5)Mass Air Flow (MAF)/Intake Air Temperature (IAT) Sensor