GMC 2003 C4C042 Owner's Manual page 337

Underhood Fuse Block
When a circuit goes out, the problem could be in either
the primary or secondary underhood fuse blocks. These
-
blocks uses blade type fuses.
Primary Underhood
Fuse Block
Both underhood
fuse blocks are
located in the engine
compartment, on the
passenger's side of
the vehicle.
To access the fuse blocks, gently squeeze both sides of
the cover to unlatch the tabs at the top. Then, unsnap
both attachments at the bottom and remove the cover.
Be sure to replace fuses with fuses of the same rating.
Do not use fuses of higher amperage than those
indicated on the fuse block.
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