Theory Of Operation
The Electronic Shift Module (ESM) performs various internal tests to verify proper controller operation. This DTC indicates that there is a loss of communication with the PRNDM display.
If the PRNDM is disconnected from the shifter on a live vehicle (battery still connected with CAN-C bus activity), there is a possibility that DTC code U114C-00 may be set to an 'Active' or 'Stored' state. After the PRNDM is replaced and the vehicle CAN-C bus has been inactive for a minimum of 30 seconds and an ignition cycle is begun by turning the vehicle into ACC or RUN state, the PRNDM may not illuminate and/or operate for a short period of time while the shifter determines if the PRNDM is present and functional. This could take up to 2 minutes if the software in the PRNDM assembly needs to be updated. After that period of time, the PRNDM will illuminate and function normally if there are no other issues. This is a normal fail-safe function of this component.
Opening a door will power up the ESM and with the PRNDM disconnected will trigger the U114C-00 DTC.
The U114C-00 DTC can be set in error if the Shifter and PRNDL are disconnected while the shifter is awake on CAN. The Shifter should be disconnected whenever the PRNDM is unplugged.