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

Horn


Object Number: 793743  Size: LF
(1)Front Impact Bar
(2)Horn
Figure 2:

Behind the Left Side of the Instrument Panel


Object Number: 600115  Size: LF
(1)Body Control Module (BCM)
(2)BCM Connectors
(3)G204
(4)G201
(5)Fuse Block I/P
(6)Horn Relay