Ratio control: Description

This function checks the integrity of the EM-CVT Ratio Control Motor by comparing the actual engine speed with the target engine speed over a period of time.

The procedure integrates a normalized version of the engine speed error for a set time period and then carries out a comparison when this time period expires. Many tests need to be performed in order for the motor to be diagnosed as faulty and, as such, a certain number of these have to fail. For this reason a safety de-bounce routine is also used by this diagnostic function.