Default methodology for recovering from loss of high resolution engine position signal

• Main Authors: Fayyad, Salem Ahmad, Maehling, Peter Hull, James, Jr., Charles O, Simpson, Kenneth M
• Format: Patent
• Language: English
• Published: 15.04.2003

This invention relates to the scheduling of timed events in an internal combustion engine based on a high resolution engine position signal, and more particularly to a method of scheduling such events when the high resolution position signal is lost or corrupted. A default engine control method for an internal combustion engine recovers from the loss of a high-resolution engine position signal by calculating a high resolution pulse period based on a recognized pattern of a low resolution engine position signal. Interrupts for signaling the execution of cycle-related control algorithms are scheduled in time based on the calculated pulse period, and pulse period errors due to changing engine speed are periodically corrected based on the timing of subsequent transitions in the low resolution position signal relative to the scheduled interrupts.