2023 Chevrolet Silverado 3500HD Fuse Box Diagram & Amperage Guide

As an ASE-certified master technician, I’ve spent plenty of time hunting down electrical gremlins in heavy-duty trucks. If your 2023 Chevrolet Silverado 3500HD is experiencing an electrical issue—whether it's a dead infotainment screen, a trailer brake fault, or an inoperative 12V outlet—the first place you should always check is the fuse box.

Today, we are going to cover everything you need to know about the 2023 Chevy Silverado 3500HD fuse box diagrams, amp ratings, and locations so you can get your heavy-duty hauler back to work.

Quick Answer: Fuse Box Locations

Before you can check a blown fuse, you need to know where to look. The 2023 Chevrolet Silverado 3500HD has three main fuse box locations:

1. Engine Compartment Fuse Block: Located under the hood on the passenger side of the engine bay, near the firewall and battery.
2. Instrument Panel Fuse Block (Left): Located on the driver's side of the dashboard, accessible by removing the side trim cover when the driver's door is open.
3. Instrument Panel Fuse Block (Right): Located on the passenger side of the dashboard, accessible by removing the side trim cover when the passenger's door is open.

Note: There is no traditional trunk or cargo fuse box on the Silverado 3500HD, though there may be dedicated inline fuses for aftermarket upfitter switches or specific trailer wiring setups depending on your exact trim.

Engine Compartment Fuse Block

The under-hood fuse block is the main power distribution center for the vehicle. It houses the high-amp relays and fuses for the powertrain, exterior lighting, and heavy-duty towing systems.

Disclaimer: Fuse configurations can vary slightly depending on your engine (6.6L Gas vs. 6.6L Duramax Diesel) and trim level (WT, LT, LTZ, High Country). Always verify with the printed legend on the inside of your fuse box lid.

Instrument Panel Fuse Block (Left / Driver Side)

This fuse panel primarily protects the interior components, driver-side electrical features, and safety systems.

Instrument Panel Fuse Block (Right / Passenger Side)

The right-side instrument panel fuse box handles infotainment, cabin climate control, power outlets, and passenger-side accessories.

How to Test a Fuse

If a component stops working, testing the fuse is a quick and easy diagnostic step. Here is how I recommend doing it:

1. Locate the Suspect Fuse: Use the printed legend on the fuse box lid (or the tables above) to find the fuse associated with your dead circuit.
2. Visual Inspection: Pull the fuse using the plastic puller tool located in the under-hood fuse block (or a pair of needle-nose pliers). Look at the metal wire inside the colored plastic housing. If the wire is broken or charred black, the fuse is blown and must be replaced.
3. Multimeter / Test Light Method: If you don't want to pull every fuse, turn the vehicle to the "ON" position (without starting the engine). Take a 12V test light and ground the clip. Touch the probe to the two tiny exposed metal test points on the top of the fuse.
   • If the light illuminates on both sides, the fuse is good.
   • If the light illuminates on one side but not the other, the fuse is blown.
4. Replace with the Exact Same Amperage: Never replace a blown fuse with one of a higher amp rating. Doing so can cause wiring to overheat and potentially start a fire.

Common Blown Fuses on this Vehicle

Heavy-duty trucks like the 3500HD are subjected to harsh conditions. Here are the fuses I see blow most often, and what you should check first:

• Trailer Lighting Fuses (Under-hood #61, #74): If you hook up to a trailer with frayed wiring or a bad ground, the truck's fuse will blow to protect its own Body Control Module. Always inspect the trailer plug and wiring before blindly replacing the fuse.
• 12V Outlet / Cigar Lighter (Right Dash #F5): Commonly blows when a faulty cell phone charger, power inverter, or air compressor is plugged into the dash. Check the accessory for shorts.
• OBD2 Port Fuse (Left Dash #F27): If your diagnostic scan tool won't power up, this is the fuse to check. It's often on the same circuit as a cigarette lighter or auxiliary power in many GM trucks.
• Blower Motor (Right Dash #F12): If your A/C or heat fan stops blowing, check this 40A fuse. However, if it blows repeatedly, you likely have a failing blower motor drawing too much amperage, or a burned-out blower motor resistor.

Always remember that replacing a fuse only fixes the symptom. If a fuse blows repeatedly, you have a short circuit or an overloaded component that needs proper diagnosis.

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