Learn about Chevrolet C3500 HD 2001-2002 fuse box and relay’s locations, functions, and maintenance tips for optimal vehicle electrical system.
The Chevrolet C3500 HD (2001-2002) is a heavy-duty pickup truck built for power and durability, often used in commercial and towing applications. Available in both regular and crew cab body styles, it offers a spacious interior for driver comfort and flexibility in handling large workloads. The robust exterior design supports high payloads, making the C3500 HD an ideal choice for tough jobs and hauling heavy cargo.
The truck’s electrical systems, which control everything from lights to engine management, rely on a well-organized fuse box and relay system. The primary fuse box is located in the engine compartment, ensuring quick access for maintenance, while additional relays are typically found near the fuse box to manage high-current components like the starter, fuel pump, and air conditioning. Regularly inspecting these components is key to preventing electrical issues and ensuring the truck performs reliably under demanding conditions.
MUST READ: DYI – How to Check Car Fuses?
(2001-2002) Chevrolet C3500 HD fuse box and relay with Diagram
WARNING
- Never replace a fuse with one that has a higher amperage rating.
- A fuse with a too-high amperage could damage the electrical part and cause a fire.
- On no account should fuses be repaired (e.g. patched up with tin foil or wire) as this may cause serious damage elsewhere in the electrical circuit or cause a fire.
- If a fuse blows repeatedly, do not keep replacing it. Instead, have the cause for the repeated short circuit or overload tracked and fixed.
- Terminal and harness assignments for individual connectors will vary depending on vehicle equipment level, model, and market.
Chevrolet C3500 HD 2001-2002 fuse assignment
Chevrolet C3500 HD Year of production: 2001, 2002
Location of Fuse Boxes
Instrument Panel Fuse Block:
The fuse block access door is on the driver’s side edge of the instrument panel. Pull off the cover to access the fuse block.
Underhood Fuse/Relay Center:
The underhood fuse/relay center is located in the rear of the engine compartment near the brake fluid reservoir.
Fuse Box Diagrams
2001
Instrument Panel Fuse Block
List of fuses in the Instrument Panel Fuse Block (2001)
| № | Usage |
|---|---|
| 1 | Stop/TCC Switch, Buzzer, CHMSL, Hazard Lamps, Stoplamps |
| 2 | Not Used |
| 3 | Courtesy Lamps, Cargo Lamp, Glove Box Lamp, Dome/Reading Lamps, Vanity Mirrors |
| 4 | Instrument Cluster, DRL Relay, Lamp Switch, Keyless Entry, Low Coolant Module, Illuminated Entry Module, DRAC (Diesel Engine) |
| 5 | Not Used |
| 6 | Cruise Control |
| 7 | Auxiliary Power Outlet |
| 8 | Crank |
| 9 | License Lamp, Parking Lamps, Taillamps, Roof Marker Lamps, Front Sidemarkers, Door Switch Illumination, Headlamp Switch Illumination |
| 10 | Not Used |
| 11 | Wiper Motor, Washer Pump |
| 12 | A/C, A/C Blower, High Blower Relay |
| 13 | Power Amp, Cigarette Lighter, Door Lock Relay |
| 14 | Cluster, Comfort Controls, Instrument Switches, Radio Illumination, Chime Module |
| 15 | DRL Relay |
| 16 | Front and Rear Turn Signals, Back-Up Lamps |
| 17 | Radio (Ignition) |
| 18 | 4WAL/VCM, ABS, Cruise Control |
| 19 | Radio (Battery) |
| 20 | PRNDL, Automatic Transmission, Speedometer, Check Gages Warning Light |
| 21 | Security/Steering |
| 22 | Not Used |
| 23 | Not Used |
| 24 | TP2 Relay (Gasoline Engine) |
| A | Power Door Lock, Keyless Entry Module |
| B | Power Windows |
Underhood Fuse/Relay Center
List of fuses in the Underhood Fuse Center (2001)
| Name | Usage |
|---|---|
| Starter Relay | Starter |
| A/C Relay | Air Conditioning |
| Fuel Pump Relay | Fuel Pump |
| Brake Lamp Relay | Brake Lamp |
| Horn Relay | Horn |
| ECM-B | Fuel Pump, PCM/VCM |
| RR DEFOG | Not Used |
| IGN-E | A/C Compressor Relay, Dual Tanks |
| HORN | Horn, Underhood Lamps |
| AUX FAN | Not Used |
| ECM-1 | Injectors, PCM/VCM, Fuel Solenoid (Diesel Engine), Fuel Control Module (Diesel Engine) |
| HTD ST-FR | Not Used |
| A/C | Air Conditioning |
| PTO | PTO Relay |
| ENG-1 | Ignition Switch, EGR, Canister Purge, EVRV Idle Coast Solenoid, MAF, Heated O2, Fuel Heater (Diesel Engine), Water Sensor (Diesel Engine), Boost Solenoid (Diesel Engine), EPR (Diesel Engine) |
| HTD ST-RR | Not Used |
| Diode | Not Used |
| LIGHTING | Headlamp and Panel Dimmer Switch, Fog and Courtesy Fuses |
| BATT | Battery, Fuse Block Busbar |
| IGN A | Ignition Switch |
| IGN B | Ignition Switch |
| ABS | Anti-Lock Brake Module |
| BLOWER | High Blower Relay |
| STOP/HAZ | Stoplamps |
| HEATED SEATS | Not Used |
2002
Instrument Panel Fuse Block
List of fuses in the Instrument Panel Fuse Block (2002)
| № | Usage |
|---|---|
| 1 | Stop/TCC Switch, Buzzer, Center High Mounted Stop Lamp, Hazard Lamps, Stoplamps |
| 2 | Not Used |
| 3 | Courtesy Lamps, Cargo Lamp, Glove Box Lamp, Dome/Reading Lamps, Vanity Mirrors |
| 4 | Instrument Cluster, DRL Relay, Lamp Switch, Keyless Entry, Low Coolant Module, Illuminated Entry Module, DRAC (Diesel Engine) |
| 5 | Not Used |
| 6 | Cruise Control |
| 7 | Auxiliary Power Outlet |
| 8 | Crank |
| 9 | License Lamp, Parking Lamps, Taillamps, Roof Marker Lamps, Front Sidemarkers, Door Switch Illumination, Headlamp Switch Illumination |
| 10 | Not Used |
| 11 | Wiper Motor, Washer Pump |
| 12 | A/C, A/C Blower, High Blower Relay |
| 13 | Power Amp, Cigarette Lighter, Door Lock Relay |
| 14 | Cluster, Comfort Controls, Instrument Switches, Radio Illumination, Chime Module |
| 15 | DRL Relay |
| 16 | Front and Rear Turn Signals, Back-Up Lamps |
| 17 | Radio (Ignition) |
| 18 | 4WAL/VCM, Antilock Braking System, Cruise Control |
| 19 | Radio (Battery) |
| 20 | PRNDL, Automatic Transmission, Speedometer, Check Gages Warning Light |
| 21 | Security/Steering |
| 22 | Not Used |
| 23 | Not Used |
| 24 | TP2 Relay (Gasoline Engine) |
| A | Power Door Lock, Keyless Entry Module |
| B | Power Windows |
Underhood Fuse/Relay Center
List of fuses in the Underhood Fuse Center (2002)
| Name | Usage |
|---|---|
| Starter Relay | Starter |
| A/C Relay | Air Conditioning |
| Fuel Pump Relay | Fuel Pump |
| Brake Lamp Relay | Brake Lamp |
| Horn Relay | Horn |
| ECM-B | Fuel Pump, PCM/VCM |
| RR DEFOG | Not Used |
| IGN-E | A/C Compressor Relay, Dual Tanks |
| HORN | Horn, Underhood Lamps |
| AUX FAN | Not Used |
| ECM-1 | Injectors, PCM/VCM, Fuel Solenoid (Diesel Engine) Fuel Control Module (Diesel Engine) |
| HTD ST-FR | Not Used |
| A/C | Air Conditioning |
| PTO | PTO Relay |
| ENG-1 | Ignition Switch, Exhaust Gas Recirculation, Canister Purge, EVRV Idle Coast Solenoid, MAF, Heated O2, Fuel Heater (Diesel Engine), Water Sensor (Diesel Engine), Boost Solenoid (Diesel Engine), EPR (Diesel Engine) |
| HTD ST-RR | Not Used |
| Diode | Not Used |
| LIGHTING | Headlamp and Panel Dimmer Switch, Fog and Courtesy Fuses |
| BATT | Battery, Fuse Block Busbar |
| IGN A | Ignition Switch |
| IGN B | Ignition Switch |
| ABS | Anti-Lock Brake Module |
| BLOWER | High Blower Relay |
| STOP/HAZ | Stoplamps |
| HEATED SEATS | Not Used |
Conclusion
The Chevrolet C3500 HD (2001-2002) is a powerful work truck with reliable functionality. Routine checks of its fuse box and relays are essential for consistent performance.
