GMC Sierra 2015 Owner's Manual page 414

Micro Usage
Relays
60 Fuel Pump
61 Upfitter 2
62 Upfitter 3
63 Upfitter 4
64 Trailer Parking
Lamps
65 Run/Crank
66 Upfitter 1
67 Fuel Pump 2
68 Air Conditioning
Control
69 Starter
Mini Relays Usage
70 Rear Window
Defogger
71 Engine Control
Module
Solid State Usage
Relay
72 Cooling Fan Clutch
Vehicle Care
Instrument Panel Fuse
Block (Left)
The left instrument panel fuse block
access door is on the driver side
edge of the instrument panel.
Pull off the cover to access the fuse
block.
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