GM Service Manual Online
For 1990-2009 cars only
Figure 1:

Heat Only


Object Number: 556972  Size: FS
HVAC Components
HVAC Air Delivery/Temperature Control Circuit Description
Heat and A/C
ILLUM and PARK LP Fuses
Ign ACC, RUN and RAP Bus Bar
ILLUM Fuse 12
HVAC Connector End Views
G203 and G204 (Pickup)
G200, G201 and G207 (Pickup)
Figure 2:

Heat and A/C


Object Number: 556973  Size: FS
HVAC Components
HVAC Air Delivery/Temperature Control Circuit Description
Heat Only
ILLUM and PARK LP Fuses
Ign ACC, RUN and RAP Bus Bar
ILLUM Fuse 12
HVAC Connector End Views
Defogger Schematic
Automatic Day-Night Mirrors Schematics
G203 and G204 (Pickup)
2000 S/T Headlight Leveling
G200, G201 and G207 (Pickup)