The diagnostic code P0605 OBDII means that a control module read memory error has been detected. This problem may be in the Powertrain Control Module (PCM) or one of the other supporting control modules. The PCM monitors other control modules at all levels of vehicle operation to control various functions.
When the code P0605 OBD2 is set, it is because the PCM is not able to monitor one or more control modules. The capacity to adjust the control module for proper vehicle operation has been disabled.