Diagnostic Aids

WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2007 GMC Yukon XL, 2007 GMC Yukon, 2007 Chevrolet Tahoe, 2007 Chevrolet Suburban, and 2007 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.

Inspect for any debris or water in the horn assembly.
Test the horn mounting hardware for proper torque. Refer to Fastener Tightening Specifications .
Inspect for debris in the joint where the horns attach to the vehicle.