Conditions for Setting the DTC
WARNING: This page is about a different car, the 2010 GMC Sierra and 2010 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The ECM detects that the engine has started and is running, but receives less than 398 or more than 402 camshaft position pulses per 100 engine cycles in 800 of 1,000 engine cycles.