Check the engine bay power distribution center first, as it contains high-amperage inserts for systems like cooling fans, starter relay, and trailer connections. Use the cover label to match slot numbers with circuit names before removing anything.
A second panel is located inside the cabin, typically on the driver side near the dashboard or behind a side cover. This area manages interior electronics such as infotainment, power outlets, lighting, and seat controls. Access usually requires opening a small trim panel without tools.
Each slot is rated by amperage, commonly 10A, 15A, 20A, and 40A. Lower ratings protect sensors and control units, while higher values handle motors and heavy loads. Installing a higher rating than specified can damage wiring or control modules.
Use a plastic puller stored in the panel cover to remove inserts safely. Inspect the internal metal strip; a visible break confirms failure. Keep spare inserts in the glove compartment to restore functions like power windows or radio without delay during roadside checks.
GMC Sierra Fuse Box Diagram Locations Layout and Circuit Assignment Guide
Locate the main power distribution center under the hood on the driver side near the battery; this unit controls high-load systems such as cooling fans, ABS module, ignition circuits, and trailer wiring.
A secondary panel sits inside the cabin, typically at the side of the dashboard or beneath it. This section handles interior systems including radio, HVAC controls, power windows, and accessory outlets.
Slot numbering is printed directly on the plastic housing and often mirrored on the cover. Match each number with the assignment chart to identify circuits like fuel pump, transmission control, or lighting systems without removing multiple inserts.
Amperage ratings vary depending on circuit load. Common values include 10A for control modules, 20A for outlets and small motors, and 30A or higher for heavy components such as blower motors or seat heaters.
Engine Bay Layout Details
The under-hood unit groups related systems in clusters. For example, cooling and engine management circuits are positioned close together, while trailer and towing connections are placed near dedicated relays for quick access during diagnostics.
Large cartridge-style inserts are used for primary protection of major systems like alternator output and main power feeds. These are separate from smaller blade-style components and require careful handling.
Cabin Panel Circuit Distribution
The interior section uses compact blade-style inserts arranged in tight rows. Circuits are grouped by function, with lighting and infotainment typically located in adjacent positions, reducing time spent tracing faults.
Keep a printed assignment chart in the glove compartment and verify each slot before removal. This prevents accidental disconnection of unrelated systems while troubleshooting issues like inactive displays or non-working switches.
Where Fuse Boxes Are Located in GMC Sierra by Model Year and Trim
Check two primary locations: under the hood near the battery and inside the cabin at the driver side dashboard edge; these areas contain nearly all circuit protection points across most model years.
For 1999–2006 trucks, placement is consistent and easy to access:
- Engine bay: mounted on the driver side close to the battery housing
- Cabin panel: behind a removable cover on the side of the dashboard
- No additional rear compartment unit used for standard configurations
For 2007–2013 models, layout remains similar with slight refinements in positioning and labeling clarity.
- Under-hood distribution center: larger housing with grouped high-load circuits
- Interior panel: positioned at dashboard side with improved access panel
- Optional auxiliary blocks added for towing packages
2014 and Newer Models
Later versions introduce more structured grouping of circuits and additional protection modules.
- Front compartment unit: sealed design with clear printed slot references
- Cabin section: relocated slightly for easier reach without tools
- Extra modules: included for advanced electronics and driver assistance systems
Trim Level Differences
Higher trims with towing or off-road packages may include extra relay carriers and added protection units near the main under-hood assembly. Base trims retain standard two-location layout. Always inspect both engine bay and interior panel when diagnosing electrical faults, as system distribution varies by equipment package.