Circuit/System Verification
WARNING: This page is about a different car, the 2009 GMC Sierra, 2009 GMC Cab & Chassis Sierra, and 2009 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
Ignition OFF, use the remote switch to engage PTO. The engine RPM should increase to the default engine speed within a few seconds.