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

Horn Assembly


Object Number: 1492975  Size: MF
(1)I/P Harness
(2)Horn Assembly
Figure 2:

Steering Wheel and Column


Object Number: 856748  Size: LF
(1)Steering Wheel Control Switch Assembly - Upper Left (STW)
(2)Passlock Sensor Connector
(3)Ignition Key Alarm Switch
(4)Ignition Lock Cylinder Control Actuator
(5)Ignition Lock Cylinder Control Actuator Connector
(6)Ignition Switch
(7)Ignition Key Cylinder
(8)Steering Wheel Control Switch Assembly - Upper Right (STW)
(9)Horn Switch
(10)Steering Wheel Control Switch Assembly - Lower Right (STW)
(11)C277
(12)Steering Wheel Control Switch Assembly - Lower Left (STW)
(13)Turn Signal/Multifunction Switch