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For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2008 🢒 Yukon XL - 4WD 🢒 Diagnostic Navigation 🢒 Vehicle Diagnostic Information 🢒 Power Moding Schematics
Figure 1:

Ignition 3 and Accessory Voltage
Object Number: 1907504 Size: FS
Master Electrical Component List
Power Mode Description and Operation
Control Module References
Ignition 2/3 Voltage
Figure 2:

Ignition 2/3 Voltage
Object Number: 2136302 Size: FS
Master Electrical Component List
Power Mode Description and Operation
Control Module References
Ignition 1 Voltage
Ignition 3 and Accessory Voltage
DLIS Fuse and Ignition Switch
RUN/CRANK Bus - AIRBAG IGN, MISC IGN and SEO/ALC Fuses
RUN/CRANK Bus - ECM-IGN and TRANS IGN 1 Fuses
RUN/CRANK Bus - AIRBAG IGN, MISC IGN and SEO/ALC Fuses
RUN/CRANK Bus - AIRBAG IGN, MISC IGN and SEO/ALC Fuses
RUN/CRANK Bus - AUX HVAC - IGN and HVAC - IGN Fuses
RUN/CRANK Bus - AUX HVAC - IGN and HVAC - IGN Fuses
G102, G104, and G108
Figure 3:

Ignition 1 Voltage
Object Number: 1907511 Size: FS
Master Electrical Component List
Power Mode Description and Operation
Control Module References
Ignition 2/3 Voltage