High idle switch

The high idle switch monitors engine temperature during the high idle warm-up period. The high idle icon appears in your rearview mirror. When the engine is warm enough, the idle returns to normal and the icon in your mirror alerts you. The high idle switch requires 2500 or 3500 models, Vortec® 6.0L V8 SFI FlexFuel engine or gaseous 6.0L V8 SFI engine and the Convenience Package. It is included with the Ambulance Package and not available with 1500 models.