Patent ID: 8457862
Filing Date: 2013-06-04
Classification: F01L

Abstract:
1. A method for controlling and diagnosing performance of a camshaft phaser in an internal combustion engine wherein the camshaft phaser includes a vaned rotor disposed within a stator for phasing of the camshaft with respect to the engine crankshaft and a locking pin disposed within the rotor for locking the rotor to the stator at a predetermined angular position of the rotor, the method comprising the steps of: a) determining when a change is needed in the position of said locking pin, wherein said position of said locking pin determines if said rotor is locked to said stator to prevent relative rotation of said rotor with said stator or if said rotor is unlocked from said stator to permit relative rotation of said rotor with said stator; b) commanding said needed change in the position of said locking pin; c) commanding said rotor to said predetermined angular position to permit said commanded locking pin position change to be carried out when said change is required; d) determining whether said commanded locking pin position change was carried out successfully; e) determining a rotor position error based on a desired and actual rotor position and; f) comparing the rotor position error to a predetermined threshold value.