Apparatus and method for controlling a variable valve mechanism

A control device for a variable valve mechanism is capable to perform a fail-safe control in a case in which a detent in any of a camshaft with a double shaft structure occurs. The control device for a variable valve mechanism includes a camshaft with a double shaft structure including an outer camshaft and an inner camshaft, whereby it is possible to adjust the phase of a minor lobe of an inner camshaft in relation to a main cam of the outer camshaft, by means of these cams at least one is operated by an intake valve and an exhaust valve of an internal combustion engine. Is an abnormality in one of the camshafts is detected, then the control means controls the phase of the cam of the other camshaft in correspondence to the determined current phase of the cam.