Theory Of Operation
WARNING: This page is about a different car, the 2024 Jeep Grand Cherokee L. However, it is still accessible from the selected car via links, so may be relevant.
The purpose of the diagnostic is to detect an engine overspeed using two different methods. First, the actual engine speed is compared to a maximum allowable engine speed threshold. Second, when a gear shift request occurs the calculated input speed of the target gear is compared to the maximum allowable engine speed threshold.