One problem related to tail light switch has been reported for the 2015 Chevrolet Impala. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2015 Chevrolet Impala based on all problems reported for the 2015 Impala.
Water filling trunk and getting the back seat carpet wet. Mold smell until I discovered the trunk needs to be drained. Found leaking gaskets on tail lights. Bumper needs to be removed. Common problem dealer will not fix under warranty. I one of the tail lights also failed. 38k miles.