Code P041, No Cam Reference Sens SGNL From IGN Control Module: Notes
WARNING: This page is about a different car, the 1995 Cadillac Eldorado. However, it is still accessible from the selected car via links, so may be relevant.
Checks for CAM reference pulses not received when 4X reference pulses are being received. This indicates a cam sensor circuit failure and Code P041 will set.