Belt Tension
WARNING: This page does not describe the selected car, but rather 11 other vehicles, including the 2003 GMC Yukon XL, 2003 GMC Yukon, 2003 GMC Savana, 2003 GMC Envoy XL, and 2003 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.
Adjustment of serpentine belt is not necessary. Belt tension is maintained by spring-tensioned idler pulley (some equipped with belt wear indicator).