GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2007 🢒 Lucerne 🢒 Power and Signal Distribution 🢒 Wiring Systems and Power Management 🢒 HVAC Schematics
Figure 1:

Power, Ground, Blower Motor Controls
Object Number: 1790017 Size: FS
Master Electrical Component List
Air Temperature Description and Operation
Control Module References
Mode and Air Temperature Controls
Rear Fuse Block B+
PRK LAMP, DRL Relays, IP HARN MDL, LT PRK LAMP, RT PRK LAMP, DRL Fuses
Underhood Fuse Block B+
RUN/CRANK Relay, TRANS IGN 3, AIRBAG IGN 3, HVAC/IPC, ECM IGN 3 Fuses
PRK LAMP, DRL Relays, IP HARN MDL, LT PRK LAMP, RT PRK LAMP, DRL Fuses
RUN/CRANK Relay, TRANS IGN 3, AIRBAG IGN 3, HVAC/IPC, ECM IGN 3 Fuses
Defogger Schematics
Hazard, Headlamp, Driver Information Display Switches, Ashtray, HVAC Control Module, Radio
G304
G300
Mode and Air Temperature Controls
Air Temperature Controls
Air Temperature Controls
G112 (L26)
Figure 2:

Mode and Air Temperature Controls
Object Number: 1790032 Size: FS
Master Electrical Component List
Air Temperature Description and Operation
Control Module References
Compressor Controls
Power, Ground, Blower Motor Controls
Power, Ground, Blower Motor Controls
Figure 3:

Compressor Controls
Object Number: 1790038 Size: FS
Master Electrical Component List
Air Temperature Description and Operation
Control Module References
Air Temperature Controls
Mode and Air Temperature Controls
High Speed Serial Data
Underhood Fuse Block B+
Underhood Fuse Block B+
G112 (L26)
G101, G110, G111, G114, G115, G302, G303, G306, G307
Figure 4:

Air Temperature Sensors
Object Number: 1790078 Size: FS
Master Electrical Component List
Air Temperature Description and Operation
Control Module References
Compressor Controls
Power, Ground, and Low Speed GMLAN
G300
Power, Ground, Blower Motor Controls
G300
Power, Ground, Blower Motor Controls