GMC 2003 Sonoma Owner's Manual page 361

Engine Compartment Fuse Block
The engine compartment fuse block is located under the
hood
on
the driver's side of the vehicle. See Engine
Compartment Overview on page 5-12 for more
information on location.
Remove the cover by turning the fastener
counterclockwise. To reinstall the fuse panel cover,
push in and turn the fastener clockwise.
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