2023 GMC Sierra 2500HD Fuse Box Diagram & Amperages

As an ASE-certified master technician, I’ve spent countless hours diagnosing electrical gremlins on heavy-duty trucks. If your 2023 GMC Sierra 2500HD has suddenly lost power to the infotainment screen, the fuel pump won't prime, or your trailer lights are out, your first stop should always be the fuse box.

Modern heavy-duty trucks like the Sierra 2500HD rely on complex electrical architectures with multiple fuse blocks protecting sensitive modules and high-draw accessories. In this guide, I will break down the fuse box locations, amperage ratings, color codes, and protected circuits to help you get your truck back on the road or the job site.

Note: The following tables represent the most common configurations for the 2023 GMC Sierra 2500HD (both gas and Duramax diesel trims). Features vary by trim (e.g., Denali, AT4, SLE) and options. Always verify against the printed legend located inside your fuse box lid before replacing a fuse.

Quick Answer: Fuse Box Locations

The 2023 GMC Sierra 2500HD features three primary fuse box locations:

1. Engine Compartment Fuse Block: Located on the passenger side of the engine compartment, near the battery and coolant reservoir.
2. Left Instrument Panel Fuse Block: Located on the driver’s side of the dashboard. You must remove the side cover (accessible when the driver's door is open) to access it.
3. Right Instrument Panel Fuse Block: Located on the passenger side of the dashboard, behind a similar side cover accessible when the passenger door is open.

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Engine Compartment Fuse Block

The under-hood fuse block handles high-amperage circuits, critical engine management components, ABS, exterior lighting, and heavy-duty towing relays.

Fuse #	Amp	Color	Circuit / Component Protected
F05	15A	Blue	Engine Control Module (ECM) / Powertrain Control Module (PCM)
F11	30A	Pink	Starter Motor (Solenoid)
F14	20A	Yellow	Fuel Pump Power Module
F17	10A	Red	Air Conditioning (A/C) Clutch
F21	60A	Yellow (J-Case)	Anti-lock Braking System (ABS) Pump
F27	30A	Pink	Trailer Brake Control Module
F31	15A	Blue	High Beam Headlights (Left/Right)
F35	10A	Red	Low Beam Headlights
F42	20A	Yellow	Trailer Parking / Tail Lights
F47	30A	Pink	Cooling Fan
F55	15A	Blue	Ignition Coils / Injectors (Gas) or Glow Plugs (Diesel logic)
F63	30A	Pink	Trailer Brake / Aux Power
F72	10A	Red	Engine Control Module (Ignition)
F85	15A	Blue	Horn

Key Relays in this Block:

• K1: Starter Relay
• K3: A/C Compressor Clutch Relay
• K5: Fuel Pump Relay
• K8: Trailer Backup Lamp Relay

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Left Instrument Panel Fuse Block (Driver Side)

This fuse block is located behind the driver-side dash panel. It primarily protects body controls, driver-focused accessories, lighting, and convenience features.

Fuse #	Amp	Color	Circuit / Component Protected
F02	10A	Red	Steering Wheel Controls / Backlight
F06	15A	Blue	Body Control Module (BCM) - Lighting
F11	15A	Blue	Instrument Cluster / Head-Up Display (if equipped)
F14	20A	Yellow	Cigar Lighter / 12V Auxiliary Power Outlet (Front)
F18	15A	Blue	Radio / Infotainment System
F22	10A	Red	Diagnostic Link Connector (OBD-II Port)
F27	15A	Blue	Brake Switch / Brake Lights
F33	10A	Red	Airbag Module (Sensing and Diagnostic Module)
F38	20A	Yellow	Power Windows (Driver / Left Rear)

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Right Instrument Panel Fuse Block (Passenger Side)

Located behind the passenger-side dash end cap, this fuse box handles passenger-side accessories, climate control components, and secondary body modules.

Fuse #	Amp	Color	Circuit / Component Protected
F04	40A	Green (J-Case)	HVAC Blower Motor
F09	20A	Yellow	12V Auxiliary Power Outlet (Rear/Console)
F12	15A	Blue	Passenger Seat Heater/Ventilation
F17	10A	Red	Passenger Airbag Indicator / Occupant Sensor
F21	20A	Yellow	Power Windows (Passenger / Right Rear)
F26	15A	Blue	Amplifier / Premium Audio System
F31	10A	Red	HVAC Controls / Actuators

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How to Test a Fuse

Before throwing parts at an electrical problem, test the fuses. Visually inspecting a fuse isn't always reliable, as micro-fractures can break the circuit without leaving a visible scorch mark.

1. Use a Test Light or Multimeter: Set your multimeter to continuity (the "beep" setting) or DC Volts. If using a test light, attach the clamp to a good metal ground.
2. Turn the Key On: For circuits that only have power when the ignition is on (like the radio or blower motor), make sure the key is in the "ON/RUN" position.
3. Probe the Test Points: Modern blade fuses have two small metal test points exposed on the top. Touch your test light or multimeter probes to these points.
4. Read the Results:
   • Test Light: It should illuminate on both test points. If it lights up on one side but not the other, the fuse is blown.
   • Multimeter (Volts): You should read battery voltage (~12.6V) on both sides.
   • Multimeter (Continuity): With the battery disconnected or the fuse removed, touching the probes to the fuse blades should produce a beep (0 ohms). No beep means a blown fuse.

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Common Blown Fuses on this Vehicle

Heavy-duty trucks work hard, and some circuits are more prone to popping than others. If you own a 2023 Sierra 2500HD, keep a close eye on these circuits:

• Trailer Lighting & Brake Fuses (Under-hood F27, F42, F63): Towing different trailers means dealing with different wiring setups. Corroded trailer plugs or shorted wires on the trailer itself will immediately pop these fuses. What to check first: Inspect the 7-way connector at the bumper for water intrusion, corrosion, or pushed-in pins. Check the trailer's wiring harness for chafing.
• 12V Auxiliary/Cigar Lighter (Left IP F14 / Right IP F09): Phone chargers, power inverters, and portable air compressors easily overload these 20-amp circuits. What to check first: Remove whatever accessory was plugged in. Look inside the 12V port for pennies or debris that might be bridging the contacts and causing a dead short.
• Fuel Pump Relay/Fuse (Under-hood F14): Especially on high-mileage gas models, a failing fuel pump will draw excessive amperage as it wears out, eventually popping the fuse. What to check first: Listen for the fuel pump prime when you turn the key. If the fuse pops immediately upon replacement, you likely have a short to ground in the pump harness or a seized pump motor.

Electrical diagnostics can get complicated quickly, especially on a truck with as many modules as the 2023 GMC Sierra 2500HD. If you've checked your fuses and are still experiencing issues, it might be time to call in a professional.

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