Chevrolet Silverado 2500 HD 2008 - 2008 GENERAL MOTORS Sierra & Silverado

Chevrolet Silverado 2500 HD 2008 - BUZZERS, RELAYS & TIMERS

Chevrolet Silverado 2500 HD 2008 BUZZERS, RELAYS & TIMERS LOCATION

Component	Location
A/C CMPRSR Relay	In underhood fuse block. See Fig. 63.
Auxiliary Battery Relay (4)	Rear of engine compartment. See Fig. 81.
Emergency Vehicle Roof Lamp Relay (5)	In roof console. See Fig. 101.
ENG EXH VLV Relay	In underhood fuse block. See Fig. 63.
FAN CNTRL Relay	In underhood fuse block. See Fig. 63.
FAN HI Relay	In underhood fuse block. See Fig. 63.
FAN LO Relay	In underhood fuse block. See Fig. 63.
FAN RLY Relay	In underhood fuse block. See Fig. 63.
FOG LAMP Relay	In underhood fuse block. See Fig. 63.
FUEL PMP Relay	In underhood fuse block. See Fig. 63.
Fuel Pump (FP) Relay (Secondary) (3)	Left side of engine compartment. See Fig. 104.
HDLP LO/HID Relay	In underhood fuse block. See Fig. 63.
Integrated Trailer Brake Controller Solid State Relay	On rear of left frame rail. See Fig. 45.
PRK LAMP Relay	In underhood fuse block. See Fig. 63.
PWR/TRN Relay	In underhood fuse block. See Fig. 63.
REAR DEFOG Relay	In underhood fuse block. See Fig. 63.
Roof Beacon Relay (11)	In overhead console. See Fig. 100.
RUN/CRNK Relay	In underhood fuse block. See Fig. 63.
Run Relay (2)	Right rear of engine compartment. See Fig. 81.
STRTR Relay	In underhood fuse block. See Fig. 63.
Trailer Brake Controller Solid State Relay (20/30 Series) (3)	Left rear frame rail. See Fig. 108.
Trailer Brake Controller Solid State Relay (31 Series) (1)	On left frame rail. See Fig. 109.

Chevrolet Silverado 2500 HD 2008 - CIRCUIT PROTECTION DEVICES

Chevrolet Silverado 2500 HD 2008 CIRCUIT PROTECTION DEVICES LOCATION

Component	Location
Fuse Block (I/P)	Left side of dash. See Fig. 19.
Fuse Block (Mobile Radio) (1)	Behind right side of dash. See Fig. 113.
Fuse Holder (Underhood) (Diesel) (2)	Right side of firewall. See Fig. 93.
Fuse Holder (Underhood) (6.6L)	Right side of firewall. See Fig. 60.
Heated Steering Fuse Holder (3)	On steering column. See Fig. 114.
Junction Block (Left I/P)	Lower left side of dash. See Fig. 19.
Junction Block (Rear Lamps)	Inside of left rear frame rail. See Fig. 20.
Junction Block (Right I/P)	In right end of dash. See Fig. 50.
Mega Fuse (2)	Right rear of engine compartment. See Fig. 92.
Underhood Fuse Block (4)	Left side of engine compartment. See Fig. 2.

Chevrolet Silverado 2500 HD 2008 - CONTROL UNITS

Chevrolet Silverado 2500 HD 2008 CONTROL UNITS LOCATION

Component	Location
Blower Motor Control Module (CJ2)	Lower right side of HVAC module. See Fig. 32.
Blower Motor Control Module (C67)	Lower right side of HVAC module. See Fig. 33.
Body Control Module (BCM)	Lower left side of dash. See Fig. 19.
Central Sequential Fuel Injection (SFI) Module (1)	Top rear of engine. See Fig. 85.
Chime Module	Center of dash, behind radio.
Electronic Brake Control Module (EBCM)	On left side of frame assembly. See Fig. 6.
Engine Control Module (ECM) (5)	Left front of engine compartment, near fan shroud. See Fig. 2 & Fig. 3.
Fuel System Control Module (FSCM)	Under rear of vehicle. See Fig. 25.
Glow Plug Control Module (GPCM) (6.6L)	Top left rear of engine. See Fig. 59.
Heated Steering Wheel Control Module (1)	In steering wheel. See Fig. 97.
Ignition Control Module (ICM) (4.3L) (5)	Rear of engine. See Fig. 85.
Inflatable Restraint Front Passenger Presence System (PPS) Module (7)	Under front passenger seat. See Fig. 39.
Inflatable Restraint Sensing & Diagnostic Module (SDM)	Under driver's seat. See Fig. 5.
Infrared Module (3)	In headliner. See Fig. 101.
Intake Air Heater (IAH) Module (6.6L)	Left front of engine. See Fig. 59.
Integrated Trailer Brake Controller (ITBC) Module	On rear of left frame rail. See Fig. 45.
Memory Seat Module (10)	Under front of driver's seat. See Fig. 38.
Power Take Off (PTO) Module (PTO) (8)	Outside of right front chassis frame. See Fig. 88.
Rear Object Sensor Control Module	At rear cargo area, behind trim panel. See Fig. 5.
Theft Deterrent Control Module	On right side of steering column. See Fig. 4.
Trailer Brake Controller Module (TBCM) (20/30 Series) (2)	Left rear frame rail. See Fig. 108.
Trailer Brake Controller Module (TBCM) (31 Series) (2)	On left frame rail. See Fig. 109.
Transfer Case Shift Control Module	Lower left side of dash. See Fig. 19.
Transmission Control Module (Allison)	Left front of engine compartment, near fan shroud. See Fig. 12.
Transmission Control Module (M30/M70/MW7) (6)	Left front of engine compartment, near fan shroud. See Fig. 2 & Fig. 3.
Vehicle Communication Interface Module (VCIM) (5)	Behind center of dash. See Fig. 94.

Chevrolet Silverado 2500 HD 2008 - MOTORS

Chevrolet Silverado 2500 HD 2008 MOTORS LOCATION

Component	Location
Air Temperature Actuator (C67)	Top middle of HVAC module. See Fig. 33.
Air Temperature Actuator (Left) (CJ2)	Bottom left of HVAC module. See Fig. 32.
Air Temperature Actuator (Right) (CJ2)	Top middle of HVAC module. See Fig. 32.
Blower Motor (CJ2)	Lower right side of HVAC module. See Fig. 32.
Blower Motor (C67)	Lower right side of HVAC module. See Fig. 33.
Cooling Fan (Left)	Left front of engine compartment. See Fig. 27.
Cooling Fan (Right	Right front of engine compartment. See Fig. 27.
Door Latch Assembly (Driver/Passenger)	In rear of respective front door.
Electronic Adjustable Pedal Assembly	Under left side of dash. See Fig. 1.
Front Axle Actuator	On front axle assembly. See Fig. 47.
Fuel Pump (Diesel) (2)	Between fuel tanks, on left frame rail. See Fig. 105.
Fuel Pump & Sender Assembly - Front (Gas) (2)	In front fuel tank. See Fig. 104.
Fuel Pump & Sender Assembly (Primary)	Inside fuel tank. See Fig. 6.
Fuel Pump & Sender Assembly - Rear (Gas +LY6) (1)	In rear fuel tank. See Fig. 104.
Fuel Pump & Sender Assembly (Short Wheel Base)	Inside fuel tank. See Fig. 26.
Intake Air Valve (6.6L) (7)	Top right front of engine. See Fig. 61.
Mode Actuator (CJ2)	Left end of HVAC module. See Fig. 32.
Mode Actuator (C67)	Left end of HVAC module. See Fig. 33.
Recirculation Actuator (CJ2)	Top right side of HVAC module. See Fig. 32.
Recirculation Actuator (C67)	Top right side of HVAC module. See Fig. 33.
Seat Adjuster Assembly (Driver) (12)	On driver's seat track. See Fig. 38.
Seat Adjuster Assembly (Passenger) (8)	On passenger's seat track. See Fig. 39.
Seat Lumbar Horizontal Motor (Driver) (5)	In driver's seat back. See Fig. 38.
Seat Lumbar Horizontal Motor (Passenger) (11)	In passenger's seat back. See Fig. 39.
Seat Lumbar Vertical Motor (Driver) (3)	In driver's seat back. See Fig. 38.
Seat Lumbar Vertical Motor (Passenger) (3)	In passenger's seat back. See Fig. 39.
Seat Recline Motor (Driver) (1)	Lower right side of driver seat back. See Fig. 38.
Seat Recline Motor (Passenger) (10)	Lower right side of passenger's seat back. See Fig. 39.
Sliding Rear Window Motor	Right rear of passenger compartment. See Fig. 30.
Starter (4.3L) (8)	Lower right rear of engine. See Fig. 84.
Starter (4.8L, 5.3L, 6.0L & 6.2L) (10)	Lower right rear side of engine. See Fig. 21.
Starter (6.6L)	Lower right rear side of engine. See Fig. 61.
Sunroof Module	In front of sunroof, above headliner.
Transfer Case Encoder Motor (NQH)	On transfer case. See Fig. 48.
Window Motor (Driver)	Inside driver's door. See Fig. 14.
Window Motor (Left Rear) (Crew Cab)	In left rear door. See Fig. 16.
Window Motor (Left Rear) (Extended Cab)	In left rear door. See Fig. 28.
Window Motor (Passenger)	Inside passenger's door. See Fig. 15.
Window Motor (Right Rear) (Crew Cab)	In right rear door. See Fig. 17.
Window Motor (Right Rear) (Extended Cab)	In right rear door. See Fig. 29.
Windshield Washer Fluid Pump	Bottom of washer fluid reservoir. See Fig. 49.
Windshield Wiper Motor (1)	Under windshield cowl, between wiper arms. See Fig. 2 & Fig. 3.

Chevrolet Silverado 2500 HD 2008 - SENDING UNITS & SENSORS

Chevrolet Silverado 2500 HD 2008 SENDING UNITS & SENSORS LOCATION

Component	Location
Accelerator Pedal Position (APP) Sensor	Above accelerator pedal. See Fig. 1.
A/C Refrigerant Pressure Sensor (4.3L) (6)	Near compressor, on A/C high pressure hose. See Fig. 92.
A/C Refrigerant Pressure Sensor (4.8L, 5.3L, 6.0L & 6.2L) (4)	Near compressor, on A/C high pressure hose. See Fig. 24.
A/C Refrigerant Pressure Sensor (6.6L)	Near compressor, on A/C high pressure hose. See Fig. 59.
Air Temperature Sensor (Lower Left) (CJ2)	Left side of HVAC module. See Fig. 32.
Air Temperature Sensor (Lower Right) (CJ2)	Lower left of HVAC module. See Fig. 32.
Air Temperature Sensor (Upper Left) (CJ2) (1)	Under upper left side of dash. See Fig. 96.
Air Temperature Sensor (Upper Right ) (CJ2) (2)	Under upper right side of dash. See Fig. 96.
Ambient Air Temperature Sensor - HVAC (CJ2) (3)	On left side of radiator support. See Fig. 91.
Ambient Air Temperature Sensor (ISRVM)	On radiator support. See Fig. 36.
Ambient Light/Sunload Sensor Assembly (4)	Top center of dash. See Fig. 95.
Automatic Transmission Input Shaft Speed (AT ISS) Sensor (MW7) (4)	Left side of transmission. See Fig. 88.
Automatic Transmission Turbine Speed Sensor (MW7) (3)	Left side of transmission. See Fig. 88.
Battery Current Sensor (1)	Right rear of engine compartment. See Fig. 92.
Brake Booster Vacuum Sensor (7)	Left rear of engine compartment. See Fig. 2 & Fig. 3.
Brake Mastery Cylinder Pressure Sensor (7)	Left rear of engine compartment. See Fig. 2 & Fig. 3.
Camshaft Position (CMP) Sensor (4.8L, 5.3L, 6.0L & 6.2L)	Front of engine, above crank pulley. See Fig. 23.
Camshaft Position (CMP) Sensor (6.6L)	Front of engine, above crank pulley. See Fig. 59.
Crankshaft Position (CKP) Sensor (4.3L) (6)	Front of engine, right of crank pulley. See Fig. 84.
Crankshaft Position (CKP) Sensor (4.8L, 5.3L, 6.0L & 6.2L) (8)	Right rear of engine. See Fig. 21.
Crankshaft Position (CKP) Sensor (6.6L)	Front of engine, right of crank pulley. See Fig. 61.
DPF Differential Pressure Sensor (4)	On frame crossmember. See Fig. 106.
Engine Coolant Temperature (ECT) Sensor 1 (6.6L)	Top front center of engine. See Fig. 59.
Engine Coolant Temperature (ECT) Sensor 2 (6.6L)	Top front center of engine. See Fig. 59.
Engine Coolant Temperature (ECT) Sensor (4.3L) (8)	Left side of engine. See Fig. 82.
Engine Coolant Temperature (ECT) Sensor (4.8L, 5.3L, 6.0L & 6.2L)	On top of engine. See Fig. 23.
Engine Oil Pressure (EOP) Sensor (4.3L) (4)	Rear of engine. See Fig. 85.
Engine Oil Pressure (EOP) Sensor (4.8L, 5.3L, 6.0L & 6.2L) (12)	Top rear of engine. See Fig. 21.
Engine Oil Pressure (EOP) Sensor/Switch (6.2L) (9)	Left side of engine near oil filter adapter. See Fig. 62.
Exhaust Gas Temperature (EGT) Sensor 1 (3)	In exhaust, upstream of catalytic converter. See Fig. 106.
Exhaust Gas Temperature (EGT) Sensor 2 (2)	In exhaust, downstream of catalytic converter. See Fig. 106.
Fuel Level Sensor - Primary (3)	In front fuel tank. See Fig. 105.
Fuel Level Sensor - Secondary (1)	In rear fuel tank. See Fig. 105.
Fuel Line Pressure Sensor (E85)	Under left side of vehicle. See Fig. 6.
Fuel Pump & Sender Assembly (Primary)	Inside fuel tank. See Fig. 6.
Fuel Rail Temperature (FRT) Sensor (6.6L)	Top left rear of engine. See Fig. 59.
Fuel Tank Pressure (FTP) Sensor (E85)	On fuel pump & sender assembly. See Fig. 6.
Fuel Tank Pressure Sensor (Short Wheel Base)	On fuel pump & sender assembly. See Fig. 26.
Heated Oxygen Sensor (HO2S) Bank 1 Sensor 1 (4.3L) (6)	Near left side of engine. See Fig. 82.
Heated Oxygen Sensor (HO2S) Bank 1 Sensor 1 (4.8L, 5.3L, 6.0L & 6.2L) (1)	Upstream of left catalytic converter. See Fig. 87.
Heated Oxygen Sensor (HO2S) Bank 1 Sensor 2 (4.3L) (5)	Near left side of engine. See Fig. 82.
Heated Oxygen Sensor (HO2S) Bank 1 Sensor 2 (4.8L, 5.3L, 6.0L & 6.2L) (4)	Downstream of left catalytic converter. See Fig. 87.
Heated Oxygen Sensor (HO2S) Bank 2 Sensor 1 (4.3L) (9)	Near right side of engine. See Fig. 84.
Heated Oxygen Sensor (HO2S) Bank 2 Sensor 1 (4.8L, 5.3L, 6.0L & 6.2L) (2)	Upstream of right catalytic converter. See Fig. 87.
Heated Oxygen Sensor (HO2S) Bank 2 Sensor 2 (4.3L) (10)	Near right side of engine. See Fig. 84.
Heated Oxygen Sensor (HO2S) Bank 2 Sensor 2 (4.8L, 5.3L, 6.0L & 6.2L) (3)	Downstream of right catalytic converter. See Fig. 87.
Inflatable Restraint Front End Sensor (Left)	On lower left radiator support. See Fig. 43.
Inflatable Restraint Front End Sensor (Right)	On lower right radiator support. See Fig. 43.
Inflatable Restraint Front Passenger Presence System (PPS) Sensor (9)	In front passenger's seat bottom. See Fig. 39.
Inflatable Restraint Front Sensor (2)	Behind center of front bumper. See Fig. 90.
Inflatable Restraint Seat Position Sensor (SPS) (Left) (11)	Right front corner of driver's seat track. See Fig. 38.
Inflatable Restraint Side Impact Sensor (SIS) (Left Front)	In driver's door. See Fig. 14.
Inflatable Restraint Side Impact Sensor (SIS) (Left Rear) (Crew Cab)	In left rear door. See Fig. 16.
Inflatable Restraint Side Impact Sensor (SIS) (Left Rear) (Extended Cab)	In left rear door. See Fig. 28.
Inflatable Restraint Side Impact Sensor (SIS) (Right Front)	In passenger's door. See Fig. 15.
Inflatable Restraint Side Impact Sensor (SIS) (Right Rear) (Crew Cab)	In right rear door. See Fig. 17.
Inflatable Restraint Side Impact Sensor (SIS) (Right Rear) (Extended Cab)	In right rear door. See Fig. 29.
Inflatable Restraint Vehicle Rollover Sensor (ASF)	Below center console. See Fig. 5.
Input & Output Speed Sensor Assembly (2)	In transmission, on control solenoid valve assembly.Fig. 89.
Input Speed Sensor (ISS) Assembly	In transmission. See Fig. 9.
Inside Air Temperature Sensor (Front) (CJ2)	Left side of headliner. See Fig. 13.
Intake Air Temperature (IAT) Sensor 2 (6.6L)	On top center of engine. See Fig. 59.
Knock Sensor (KS) 1 (4.3L) (7)	Lower left side of engine. See Fig. 82.
Knock Sensor (KS) 1 (4.8L, 5.3L, 6.0L & 6.2L)	Lower left side of engine. See Fig. 23.
Knock Sensor (KS) 2 (4.3L) (7)	Lower right side of engine. See Fig. 84.
Knock Sensor (KS) 2 (4.8L, 5.3L, 6.0L & 6.2L) (7)	Lower right side of engine. See Fig. 21.
Manifold Absolute Pressure (MAP) Sensor (4.3L) (2)	Top rear of engine. See Fig. 85.
Manifold Absolute Pressure (MAP) Sensor (4.8L, 5.3L, 6.0L & 6.2L) (4)	On top of intake manifold. See Fig. 21.
Manifold Absolute Pressure (MAP) Sensor (6.6L)	On top of intake manifold. See Fig. 59.
Mass Air Flow (MAF)/Intake Air Temperature (IAT) Sensor (4.3L) (2)	Right front of engine. See Fig. 84.
Mass Air Flow (MAF)/Intake Air Temperature (IAT) Sensor (4.8L, 5.3L, 6.0L & 6.2L) (5)	Right front of engine compartment. See Fig. 24.
Mass Air Flow (MAF)/Intake Air Temperature (IAT) Sensor (6.6L) (6)	Front of engine. See Fig. 61.
Object Sensor (Left Rear Corner)	Left corner of rear bumper. See Fig. 37.
Object Sensor (Left Rear Middle)	Left side of rear bumper. See Fig. 37.
Object Sensor (Right Rear Corner)	Right corner of rear bumper. See Fig. 37.
Object Sensor (Right Rear Middle)	Right side of rear bumper. See Fig. 37.
Outside Moisture Sensor (3)	Near inside rearview mirror mount. See Fig. 102.
Rotational Position Sensor (NQH)	On transfer case. See Fig. 48.
Seat Lumbar Horizontal Motor Position Sensor (Driver) (6)	In driver's seat back. See Fig. 38.
Seat Lumbar Vertical Motor Position Sensor (Driver) (2)	In driver's seat back. See Fig. 38.
Seat Recline Position Sensor (Driver) (7)	In driver's seat back. See Fig. 38.
Steering Angle Sensor	On steering column. See Fig. 4.
Turbocharger Vane Position Sensor (6.6L)	On left side of engine. See Fig. 62.
Vehicle Speed Sensor (VSS) (MW7) (6)	Rear of transmission. See Fig. 88.
Vehicle Speed Sensor (VSS) (NQG)	On transfer case tailshaft housing. See Fig. 46.
Vehicle Speed Sensor (VSS) (NQH)	On transfer case tailshaft housing. See Fig. 48.
Vehicle Speed Sensor (VSS) (4L60-E)	On transmission tailshaft housing. See Fig. 9.
VSS Sensor	On transfer case tailshaft housing. See Fig. 11.
Water In Fuel Sensor (6.6L)	Right side of engine. See Fig. 61.
Wheel Speed Sensor (WSS) (Left Front)	On left front steering knuckle. See Fig. 7.
Wheel Speed Sensor (WSS) (Left Rear)	On left rear brake backing plate. See Fig. 8.
Wheel Speed Sensor (WSS) (Right Front)	On right front steering knuckle. See Fig. 7.
Wheel Speed Sensor (WSS) (Right Rear)	On right rear brake backing plate. See Fig. 8.
YAW Rate & Lateral Acceleration Sensor	Under center console trim panel. See Fig. 5.

Chevrolet Silverado 2500 HD 2008 - SOLENOIDS & SOLENOID VALVES

Chevrolet Silverado 2500 HD 2008 SOLENOIDS & SOLENOID VALVES LOCATION

Component	Location
A/C Compressor Clutch (4.3L) (9)	On front of A/C compressor. See Fig. 82.
A/C Compressor Clutch (4.8L, 5.3L, 6.0L & 6.2L) (3)	On front of A/C compressor. See Fig. 24.
A/C Compressor Clutch (6.6L)	On front of A/C compressor. See Fig. 59.
Camshaft Actuator Solenoid (6.0L & 6.2L) (1)	Front of engine. See Fig. 86.
Evaporative Emission (EVAP) Canister Purge Solenoid Valve (4.3L) (1)	Top left rear of engine. See Fig. 84.
Evaporative Emission (EVAP) Canister Purge Solenoid Valve (4.8L, 5.3L, 6.0L & 6.2L)	On intake manifold. See Fig. 23.
Evaporative Emissions (EVAP) Canister Vent Solenoid Valve (E85)	Under rear of vehicle. See Fig. 6.
Evaporative Emissions (EVAP) Canister Vent Solenoid Valve (Short Wheel Base)	Under rear of vehicle. See Fig. 26.
Exhaust Gas Recirculation (EGR) Valve (6.6L)	On top right side of engine. See Fig. 61.
Fuel Injector 1 (4.3L) (6)	Top of left cylinder bank. See Fig. 83.
Fuel Injector 1 (4.8L, 5.3L, 6.0L & 6.2L)	Top of left cylinder bank. See Fig. 22.
Fuel Injector 1 (6.6L)	Top of right cylinder bank. See Fig. 61.
Fuel Injector 2 (4.3L) (1)	Top of right cylinder bank. See Fig. 83.
Fuel Injector 2 (4.8L, 5.3L, 6.0L & 6.2L)	Top of right cylinder bank. See Fig. 22.
Fuel Injector 2 (6.6L)	Top of left cylinder bank. See Fig. 62.
Fuel Injector 3 (4.3L) (5)	Top of left cylinder bank. See Fig. 83.
Fuel Injector 3 (4.8L, 5.3L, 6.0L & 6.2L)	Top of left cylinder bank. See Fig. 22.
Fuel Injector 3 (6.6L)	Top of right cylinder bank. See Fig. 61.
Fuel Injector 4 (4.3L) (2)	Top of right cylinder bank. See Fig. 83.
Fuel Injector 4 (6.6L)	Top of left cylinder bank. See Fig. 62.
Fuel Injector 5 (4.3L) (4)	Top of left cylinder bank. See Fig. 83.
Fuel Injector 5 (4.8L, 5.3L, 6.0L & 6.2L)	Top of left cylinder bank. See Fig. 22.
Fuel Injector 5 (6.6L)	Top of right cylinder bank. See Fig. 61.
Fuel Injector 6 (4.3L) (3)	Top of right cylinder bank. See Fig. 83.
Fuel Injector 6 (4.8L, 5.3L, 6.0L & 6.2L)	Top of right cylinder bank. See Fig. 22.
Fuel Injector 6 (6.6L)	Top of left cylinder bank. See Fig. 62.
Fuel Injector 7 (4.8L, 5.3L, 6.0L & 6.2L)	Top of left cylinder bank. See Fig. 22.
Fuel Injector 7 (6.6L)	Top of right cylinder bank. See Fig. 61.
Fuel Injector 8 (4.8L, 5.3L, 6.0L & 6.2L)	Top of right cylinder bank. See Fig. 22.
Fuel Injector 8 (6.6L)	Top of left cylinder bank. See Fig. 62.
Shift Interlock Solenoid	On steering column. See Fig. 4.
Torque Converter Clutch Pulse Width Modulation (TCC PWM) Solenoid Valve	In transmission. See Fig. 9.
Torque Converter Clutch (TCC) Solenoid Valve	In transmission. See Fig. 9.
Turbocharger Vane Position Control Solenoid Valve (6.6L)	Top rear of engine. See Fig. 59.
1-2 Shift Solenoid (SS) Valve	In transmission. See Fig. 9.
2-3 Shift Solenoid (SS) Valve	In transmission. See Fig. 9.
3-2 Shift Solenoid (SS) Valve Assembly	In transmission. See Fig. 9.

Chevrolet Silverado 2500 HD 2008 - SWITCHES

Chevrolet Silverado 2500 HD 2008 SWITCHES LOCATION

Component	Location
A/C Low Pressure Switch (4.3L) (3)	On right side of A/C accumulator. See Fig. 92.
A/C Low Pressure Switch (4.8L, 5.3L, 6.0L & 6.2L) (2)	On right side of A/C accumulator. See Fig. 24.
A/C Low Pressure Switch (6.6L)	On right side of A/C accumulator. See Fig. 58.
Brake Fluid Level Switch (8)	On master cylinder. See Fig. 2 & Fig. 3.
Engine Coolant Level Switch (6.6L)	On bottom of surge tank. See Fig. 58.
Engine Oil Level Switch (4.8L, 5.3L, 6.0L & 6.2L) (9)	On right side of engine oil pan. See Fig. 21.
Engine Oil Level Switch (6.6L) (10)	On left side of engine oil pan. See Fig. 62
Hood Ajar Switch	Part of hood latch assembly. See Fig. 36.
Ignition Switch	In upper steering column. See Fig. 4.
Internal Mode Switch (3)	In transmission, on control solenoid valve assembly. See Fig. 89.
Park Brake Switch	On park brake pedal assembly. See Fig. 35.
Park/Neutral Position (PNP) Switch	On left rear side of transmission. See Fig. 10.
Stop Lamp Switch	Top of brake pedal assembly. See Fig. 1.
Transfer Case Shift Control Switch	On top left of transfer case. See Fig. 46.
Turn Signal Multifunction Switch	On left side of steering column. See Fig. 4.
Washer Fluid Level Switch	Bottom of washer fluid reservoir. See Fig. 49.

Chevrolet Silverado 2500 HD 2008 - MISCELLANEOUS

Chevrolet Silverado 2500 HD 2008 MISCELLANEOUS LOCATION

Component	Location
Audio Amplifier (3)	Under rear of center console. See Fig. 98.
Camper Trailer Blunt Cuts (UY2) (11)	On left rear body mount. See Fig. 107.
Cellular/Navigation Antenna (2)	Left front of roof. See Fig. 99.
Cellular/Navigation & Digital Radio Antenna (2)	Left front of roof. See Fig. 99.
Cellular Telephone Microphone	In overhead console. See Fig. 13.
Data Link Connector (DLC)	Lower left side of dash. See Fig. 18.
Digital Radio Receiver (6)	Behind right end of dash. See Fig. 94.
Door Latch Assembly (Driver)	Rear of driver's door. See Fig. 14.
Door Latch Assembly (Left Rear) (Crew Cab)	Rear of left rear door. See Fig. 16.
Door Latch Assembly (Passenger)	Rear of passenger's door. See Fig. 15.
Door Latch Assembly (Right Rear) (Crew Cab)	Rear of right rear door. See Fig. 17.
Emergency Vehicle Wiring Blunt Cuts (4)	In roof console. See Fig. 101.
Fuel Heater (6.6L)	Right side of engine, near fuel filter. See Fig. 59.
Generator (Left) (6.6L)	Upper left front of engine. See Fig. 59.
Generator (Right) (6.6L)	Upper right front of engine. See Fig. 59.
Generator (4.3L) (1)	Top front of engine. See Fig. 82.
Generator (4.8L, 5.3L, 6.0L & 6.2L)	Upper left front of engine. See Fig. 23.
GMLAN Terminator	At left side of rear chassis crossmember. See Fig. 20.
Heated Seat Element (Driver Back)	In driver's seat back. See Fig. 41.
Heated Seat Element (Driver Cushion)	In driver's seat cushion. See Fig. 41.
Heated Seat Element (Passenger Back)	In passenger's seat back. See Fig. 42.
Heated Seat Element (Passenger Cushion)	In passenger's seat cushion. See Fig. 42.
Horn (Left)	Lower left front of vehicle. See Fig. 34.
Horn (Right)	Lower right front of vehicle. See Fig. 34.
Ignition Coil 1 (4.8L, 5.3L, 6.0L & 6.2L)	Upper left side of engine. See Fig. 22.
Ignition Coil 2 (4.8L, 5.3L, 6.0L & 6.2L) (6)	Upper right side of engine. See Fig. 21.
Ignition Coil 3 (4.8L, 5.3L, 6.0L & 6.2L)	Upper left side of engine. See Fig. 22.
Ignition Coil 4 (4.8L, 5.3L, 6.0L & 6.2L) (3)	Upper right side of engine. See Fig. 21.
Ignition Coil 5 (4.8L, 5.3L, 6.0L & 6.2L)	Upper left side of engine. See Fig. 22.
Ignition Coil 6 (4.8L, 5.3L, 6.0L & 6.2L) (2)	Upper right side of engine. See Fig. 21.
Ignition Coil 7 (4.8L, 5.3L, 6.0L & 6.2L)	Upper left side of engine. See Fig. 22.
Ignition Coil 8 (4.8L, 5.3L, 6.0L & 6.2L) (1)	Upper right side of engine. See Fig. 21.
Inflatable Restraint I/P Module	Top right side of dash.
Inflatable Restraint Roof Rail Module (Left) (Extended & Crew Cab)	Behind left side of headliner trim. See Fig. 31.
Inflatable Restraint Roof Rail Module (Left) (Regular Cab)	Behind left side of headliner trim. See Fig. 44.
Inflatable Restraint Roof Rail Module (Right) (Extended & Crew Cab)	Behind right side of headliner trim. See Fig. 31.
Inflatable Restraint Roof Rail Module (Right) (Regular Cab)	Behind right side of headliner trim. See Fig. 44.
Inflatable Restraint Steering Wheel Module	In steering wheel.
Inflatable Restraint Steering Wheel Module Coil	Behind steering wheel. See Fig. 4.
Information Center Telltale Assembly	Top right rear of passenger compartment. See Fig. 30.
Mobile Radio Blunt Cuts (10)	Under center console. See Fig. 113.
Noise Compensation Microphone (5)	Left side of center console. See Fig. 98.
Power Brake Booster (2)	Left rear of engine compartment. See Fig. 2 & Fig. 3.
Remote Control Door Lock Receiver (RCDLR)	Top rear of passenger compartment. See Fig. 40.
Roof Mounted Beacon Blunt Cuts (TRW) (10)	In overhead console. See Fig. 100.
Seat Belt Pretensioner (Driver) (1)	On left "B" pillar. See Fig. 103.
Seat Belt Pretensioner (Passenger) (2)	On right "B" pillar. See Fig. 103.
Trailer Connector	At rear of vehicle. See Fig. 20.
Valve Lifter Oil Manifold (VLOM) Assembly (11)	Below intake manifold. See Fig. 21.
Windshield Washer Solvent Heater (3)	Left rear corner of engine compartment. See Fig. 2 & Fig. 3.

Chevrolet Silverado 2500 HD 2008 - CONNECTORS

Chevrolet Silverado 2500 HD 2008 CONNECTORS LOCATION

Component	Location
X100 (Black, 8 Pin)	Left front corner of engine compartment. See Fig. 64.
X103 (Black, 16 Pin)	Left side of engine compartment. See Fig. 64.
X106 (Black, 8 Pin)	Right front corner of engine compartment. See Fig. 64.
X107 (Gray, 40 Pin) (5)	Left rear of engine. See Fig. 93.
X108 (Black, 40 Pin) (4)	Left rear of engine. See Fig. 93.
X109 (-NQF/-NQH) (Black, 24 Pin)	Below underhood fuse block. See Fig. 60.
X109 (NQF/NQH) (Black, 40 Pin) (7)	Below underhood fuse block. See Fig. 68.
X110 (Black, 4 Pin)	Engine harness to front axle harness, between first & second body mount. See Fig. 47.
X111 (Light Gray, 7 Pin) (2)	Above left engine rocker cover. See Fig. 110.
X112 (4.3L) (Black, 3 Pin) (10)	Right front of engine. See Fig. 65.
X112 (4.8L & 5.3L) (Black, 3 Pin) (3)	Lower front of engine. See Fig. 86.
X112 (6.0L & 6.2L) (Black, 5 Pin) (3)	Lower front of engine. See Fig. 86.
X113 (Diesel) (Black, 6 Pin)	Engine jumper harness to engine harness.
X113 (Light Gray, 7 Pin)	Above right engine rocker cover. See Fig. 67.
X115 (Natural, 24 Pin)	Chassis harness to I/P harness, left side of chassis. See Fig. 78.
X116 (Black, 1 Pin)	Battery positive harness to brake clutch harness.
X117 (Black, 4 Pin)	Fuel rail pressure sensor jumper harness to engine harness.
X121 (Black, 1 Pin)	Battery negative harness to battery positive harness.
X122 (Black, 4 Pin) (5)	Right rear of engine compartment. See Fig. 81.
X123 (Black, 12 Pin)	Below under hood fuse block. See Fig. 60.
X124 (Black, 16 Pin) (7)	Outside of right front chassis frame. See Fig. 88.
X125 (Gray, 4 Pin) (1)	Outside of right front chassis frame. See Fig. 111.
X126 (Gray, 12 Pin) (8)	Left side of engine compartment. See Fig. 68.
X127 (Black, 2 Pin) (3)	Top front of engine. See Fig. 93.
X128 (3 Pin)	Fuel pressure regulator harness to engine harness.
X175 (MW7) (Gray, 20 Pin) (2)	Rear of engine. See Fig. 65.
X175 (M30, M70) (Gray, 20 Pin) (2)	Rear of engine. See Fig. 65.
X200 (Yellow, 4 Pin)	I/P harness to body harness, behind left kick panel. See Fig. 70.
X201 (Gray, 22 Pin) (1)	On steering column. See Fig. 114.
X202 (Black, 30 Pin)	I/P harness to body harness, behind left kick panel. See Fig. 70.
X203 (Black, 8 Pin) (2)	In I/P harness to headliner harness, near left "A" pillar. See Fig. 69.
X204 (Black, 12 Pin) (3)	Headliner harness to I/P harness, near left "A" pillar. See Fig. 69.
X205 (Black, 16 Pin)	I/P harness to brake/clutch harness, near right "A" pillar. See Fig. 70.
X206 (Black, 8 Pin) (5)	Behind right side of dash. See Fig. 69.
X207 (Black, 1 Pin)	I/P harness to I/P harness.
X211 (Black, 40 Pin) (8)	Under center console. See Fig. 69.
X212 (Black, 16 Pin) (4)	Behind left side of dash. See Fig. 69.
X214 (Black, 1 Pin) (7)	Behind right side of dash. See Fig. 113.
X219 (Black, 1 Pin) (6)	Behind right side of dash. See Fig. 113.
X220 (Black, 8 Pin) (7)	Near left body mount. See Fig. 115.
X224 (Black, 3 Pin)	Brake clutch harness to beacon harness.
X225 (Black, 1 Pin)	Brake clutch harness to battery positive harness.
X226 (Black, 1 Pin) (11)	Under left side of dash. See Fig. 113.
X227 (Black, 2 Pin)	LED indicator harness to SPO theft harness.
X228 (Black, 1 Pin)	Beacon harness to chassis harness.
X275 (Yellow, 4 Pin)	Lower left side of dash, near steering column. See Fig. 72.
X276 (Light Green, 2 Pin) (2)	On steering column. See Fig. 114.
X277 (Light Green, 2 Pin) (4)	On steering column. See Fig. 114.
X300 (Diesel) (Black, 10 Pin) (1)	Left rear of transmission. See Fig. 88.
X300 (4.3L) (Black, 8 Pin)	Left side of frame, in front of EBCM. See Fig. 66.
X303 (-AN3) (Black, 6 Pin)	Body harness to driver seat harness, under driver's seat. See Fig. 72.
X303 (AN3) (Black, 30 Pin)	Body harness to driver seat harness, under driver's seat. See Fig. 72.
X304 (Black, 16 Pin)	Headliner harness to overhead console harness, front center of roof. See Fig. 77.
X305 (-AN3) (Black, 8 Pin)	Under passenger's seat. See Fig. 72.
X305 (AN3) (Black, 30 Pin)	Under driver's seat. See Fig. 72.
X306 (Black, 8 Pin)	Headliner harness to right "A" pillar harness.
X309 (Black, 8 Pin)	Body harness to console harness, in front of audio amplifier. See Fig. 75.
X313 (Black, 5 Pin) (9)	In overhead console. See Fig. 100.
X318 (Black, 3 Pin)	Headliner harness to CHMSL harness. See Fig. 77.
X319 (Black, 2 Pin)	Body harness to console harness. See Fig. 71.
X320 (Black, 4 Pin)	Body harness to sliding rear window jumper harness. See Fig. 74.
X321 (Black, 3 Pin)	Body harness to headliner harness. See Fig. 73.
X322 (Black, 4 Pin)	Body harness to UPA jumper harness. See Fig. 74.
X324 (Black, 18 Pin) (4)	In driver's seat back. See Fig. 38.
X325 (Black, 6 Pin) (2)	In passenger's seat back. See Fig. 39.
X408 (Black, 8 Pin)	Left rear corner of vehicle. See Fig. 78.
X414 (Black, 7 Pin) (1)	Left rear of frame. See Fig. 107.
X415 (Light Gray, 2 Pin) (1)	Under left rear of cargo box. See Fig. 118.
X416 (Black, 2 Pin) (8)	Under left rear of cargo box. See Fig. 118.
X500 (Black, 10 Pin)	Body harness to left front door harness, behind left kick panel. See Fig. 72.
X501 (Black, 10 Pin)	Body harness to left front door harness, behind left kick panel. See Fig. 72.
X502 (Black, 2 Pin)	Left front door harness to body harness, behind left kick panel. See Fig. 76.
X600 (Black, 10 Pin)	Passenger door harness to body harness, behind right kick panel. See Fig. 72.
X601 (Black, 2 Pin)	Passenger door harness to body harness, behind right kick panel. See Fig. 72.
X700 (Crew Cab) (Black, 16 Pin)	Body harness to left rear door, in left "B" pillar. See Fig. 76.
X700 (Extended Cab) (Black, 12 Pin)	Left rear door to body harness, in left "B" pillar. See Fig. 73.
X800 (Crew Cab) (Black, 16 Pin)	Body harness to right rear door, in right "B" pillar. See Fig. 76.
X800 (Extended Cab) (Black, 12 Pin)	Right rear door to body harness, in right "B" pillar. See Fig. 74.

Chevrolet Silverado 2500 HD 2008 - GROUNDS

Chevrolet Silverado 2500 HD 2008 GROUNDS LOCATION

Component	Location
G100	On lower left radiator support. See Fig. 51.
G101	On lower right radiator support. See Fig. 51.
G102	On lower left front of engine. See Fig. 52.
G102 (6.6L)	On lower left front of engine. See Fig. 62.
G103	On front of right cylinder head. See Fig. 53.
G104	Front of left cylinder head. See Fig. 54.
G106 (4.3L) (3)	Right rear of engine. See Fig. 85.
G105 (6.6L) (11)	Lower left side of engine. See Fig. 61.
G106 (6.6L) (12)	Lower left side of engine. See Fig. 62.
G107	Top left rear of engine. See Fig. 54.
G108	On left side of firewall. See Fig. 54.
G110	Left side of firewall. See Fig. 54.
G111	On left side of firewall. See Fig. 54.
G200	On right front corner of HVAC module. See Fig. 32.
G201	Upper left corner of dash. See Fig. 55.
G300	Below driver's door, on body mount. See Fig. 56.
G301	Below left side of passenger's seat. See Fig. 57.
G302	Below right side of passenger's seat. See Fig. 57.
G303	On lower left "B" pillar. See Fig. 57.
G304	On lower right "B" pillar. See Fig. 57.
G307	At right rear corner of passenger compartment. See Fig. 76.
G401	On left rear body mount. See Fig. 78.

Chevrolet Silverado 2500 HD 2008 - SPLICES

Chevrolet Silverado 2500 HD 2008 SPLICES LOCATION

Component	Location
JX221 (Splice Pack)	In the I/P harness, behind left side of dash.
JX223 (Splice Pack)	In I/P extension harness, behind left side of dash.
JX339 (Splice Pack)	In body harness, below passenger seat.
J100	In forward lamp harness, 7 cm from ambient air temperature sensor breakout. See Fig. 64.
J101	In forward lamp harness. See Fig. 64.
J102 (GMC)	In left headlamp harness.
J103 (GMC)	In right headlamp harness.
J104 (1)	In engine harness, 5 cm from engine control module connector breakout. See Fig. 112.
J105 (4)	In engine harness, 12 cm from ECT sensor breakout. See Fig. 65.
J106 (4.3L) (5)	In engine harness, 23 cm from MAP sensor breakout. See Fig. 65.
J106 (4.8L, 5.3L, 6.0L & 6.2L)	In engine harness, 23 cm from MAP sensor breakout. See Fig. 67.
J107	In ignition coil jumper harness, between ignition coils 5 & 7.
J108	In ignition coil jumper harness, between ignition coils 5 & 7.
J109	In ignition coil jumper harness, 5 cm from X111 breakout.
J110	In ignition coil jumper harness, between ignition coils 4 & 2.
J111	In ignition coil jumper harness, between ignition coils 4 & 2.
J112	In ignition coil jumper harness, 5 cm from X111 breakout.
J113 (2)	In I/P harness, in X103 breakout 7 cm from main harness assembly. See Fig. 68.
J116	In automatic transmission harness, 12 cm from 1-2 shift solenoid valve breakout.
J125	In transmission harness.
J127	In PTO jumper harness.
J128 (3)	In engine harness. See Fig. 65.
J129	In PTO jumper harness.
J130 (6)	In engine harness. See Fig. 65.
J132 (4)	In engine chassis harness. See Fig. 112.
J133 (PTO) (5)	In engine chassis harness. See Fig. 112.
J134 (Diesel)	In engine harness.
J135 (Diesel)	In engine harness.
J136 (Diesel)	In engine harness.
J137 (Diesel)	In engine harness.
J138	In PTO jumper harness.
J139	In PTO jumper harness.
J140	In PTO jumper harness.
J141	In PTO jumper harness.
J142	In PTO jumper harness.
J143	In transmission harness.
J144	In transmission harness.
J145	In auxiliary battery harness.
J171 (Diesel)	In engine harness.
J175 (Diesel)	In engine harness.
J200	In I/P harness, 14 cm from left I/P junction block breakout. See Fig. 70.
J201	In I/P harness, in headlight & dimmer switch breakout. See Fig. 70.
J203	In I/P harness, 13 cm from radio connector breakout. See Fig. 70.
J204	In instrument panel harness, 19 cm after radio connector breakout.
J206	In I/P harness, 14.5 cm from X200 breakout. See Fig. 70.
J207	In instrument panel harness, in transfer case shift control module connector breakout. See Fig. 70.
J209 (5)	In fuse block jumper harness. See Fig. 113.
J210 (8)	In fuse block jumper harness. See Fig. 113.
J211 (9)	In fuse block jumper harness. See Fig. 113.
J212	In steering column harness.
J213	In steering column harness.
J214	In steering wheel harness, 4 cm from inflatable restraint steering wheel module coil X2.
J215	In steering column harness.
J216	In the steering column harness.
J217	In steering wheel harness, 9 cm from inflatable restraint steering wheel module coil X2.
J218	In steering wheel harness, 9 cm from inflatable restraint steering wheel module coil X2.
J219 (4)	In fuse block jumper harness. See Fig. 113.
J220	In fuse block jumper harness.
J222	In instrument panel harness.
J223 (1)	In steering wheel harness. See Fig. 69.
J224 (3)	In fuse block jumper harness. See Fig. 113.
J227	In SPO theft harness.
J228	In SPO theft harness.
J229	In SPO theft harness.
J300	In chassis harness, 15 cm from G300 breakout. See Fig. 78.
J301	In body harness. See Fig. 76.
J302	In body harness, 22 cm from G301 breakout. See Fig. 74.
J303	In body harness, 30 cm from G301 breakout below center console. See Fig. 72.
J304	In body harness, 14 cm from passenger seat in-line connector breakout. See Fig. 72.
J305 (-AG1)	In driver seat harness, 12.5 cm from driver seat belt buckle.
J305 (+AN3)	In driver seat harness, 4 cm in X303 breakout.
J306	In driver seat harness, 20 cm from X303.
J309	In driver seat harness, 20 cm from X303.
J310	In driver seat harness, 5 cm from driver seat adjuster assembly.
J311	In driver seat harness, 5 cm from memory seat module X4 breakout.
J312	In driver seat harness, 5 cm from driver seat belt buckle.
J314	In passenger seat harness, 20 cm from X305.
J316	In passenger seat harness, 5 cm from X305 breakout.
J322 (7)	In overhead console harness, 5 cm from X304 breakout. See Fig. 100.
J323 (8)	In overhead console harness, 4 cm from X304 breakout. See Fig. 100.
J324	In sunroof harness, 3 cm from sunroof switch breakout.
J327	In headliner harness, 15 cm from front inside air temperature sensor breakout. See Fig. 77.
J328	In headliner harness, 5 cm from front inside air temperature sensor breakout. See Fig. 77.
J330	In console harness, 12 cm from audio amplifier breakout.
J331	In chassis harness. See Fig. 78.
J334	In right "A" pillar harness.
J335	In sliding rear window jumper harness. See Fig. 79.
J336	In sliding rear window jumper harness. See Fig. 79.
J338 (4.3L)	In chassis harness. See Fig. 78.
J340	In driver seat jumper harness, 5 cm in X324 breakout.
J341	In driver seat jumper harness, 10 cm into X324 breakout.
J342	In seat position sensor harness.
J343	In seat position sensor harness.
J403	License lamp harness, 28 cm from left rear object sensors. See Fig. 80.
J404	License lamp harness, 20 cm from right rear object sensors. See Fig. 80.
J410 (UY2) (10)	In camper harness, 232.5 cm from X414 breakout. See Fig. 107.
J410 (823) (10)	In camper harness, 7 cm from back-up alarm breakout. See Fig. 107.
J411	In chassis harness.
J412 (2)	In right hip lamp harness, 7.5 cm from right rear clearance lamp breakout. See Fig. 118.
J413 (7)	In left hip lamp harness, 17.5 cm from left rear clearance lamp breakout. See Fig. 118.
J414 (8)	In camper harness. See Fig. 107.
J415 (4)	In camper harness, 109.5 cm from X414 breakout. See Fig. 107.
J416 (6)	In camper harness, 129.5 cm from X414 breakout. See Fig. 107.
J418 (6)	In left hip lamp harness, 7.5 cm from left rear clearance lamp breakout. See Fig. 118.
J419 (3)	In right hip lamp harness, 17.5 cm from right rear clearance lamp breakout. See Fig. 118.
J420	In camper harness, 59.5 cm from X414 breakout. See Fig. 78.
J421 (9)	In camper harness, 205 cm from X414 breakout. See Fig. 107.
J422	In chassis harness.
J423 (4)	In the chassis harness. See Fig. 115.
J500	In driver's outside rearview mirror jumper.
J501	In driver's outside rearview mirror jumper.
J502 (3)	In left front door harness. See Fig. 116.
J600	In passenger's outside rearview mirror jumper.
J601	In passenger's outside rearview mirror jumper.
J602	In right front door harness.
J603 (6)	In right front door harness. See Fig. 117.
J604 (1)	In right front door harness. See Fig. 117.