Theory Of Operation
WARNING: This page is about a different car, the 2020 Jeep Renegade. However, it is still accessible from the selected car via links, so may be relevant.
The Electronic Shift Module (ESM) monitors the Shift Indicator LED circuits for electrical failures. If an open circuit, short to ground, or short to voltage is detected on any of these circuits, A DTC will set and the Shift Indicator LEDs will be disabled.