One problem related to front seat heater/cooler has been reported for the 2018 Honda FIT. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2018 Honda FIT based on all problems reported for the 2018 FIT.
A few months after purchasing this vehicle (new) in fall of 2017 I noticed that the drivers seat was uncomfortably warm. I took it back to the dealer I purchased the car from and the service dept. Could find nothing wrong with the seat heater. I then took the car to another dealer, that service dept. Took an extensive check and again I was told all was working fine and they fixed nothing. However, after that second service the seat was comfortable and I had no complaint until about a month ago when the seat again became uncomfortably warm (with the heater on off). I took it to the second dealership, the person in the service dept. Took the car for a drive around town and said that the seat "retained more heat than his vehicle or others he drove) he didn't feel anything was wrong, so no one worked on checking out the wiring or anything and it is still uncomfortable to drive.