Q: trans hot idle engine in cadillac sts 2005 mean and the car keep kicking on shifting

Check the fluid level to be sure it is not either too high or too low. If the fluid level is correct, the high temperature is due to a malfunction such as a slipping clutch or band. That, in turn could be due to inadequate hydraulic pressure, internal hydraulic leaks, and so forth. In some cases, the causes will be evident once a scan tool is applied that can report real time engine and transmission operating parameters. If you desire that a professional mechanic resolve this for you, that is get the underlying fault pinpointed, please request a warning light diagnostic. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.