One problem related to front seat heater/cooler has been reported for the 2008 Mazda MAZDA6. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2008 Mazda MAZDA6 based on all problems reported for the 2008 MAZDA6.
December 14, 2015 around 6:40pm I was driving home from work on highway 275e at approximately 70 mph approaching the 71n exit ramp . Car and driver's seat heater had been running about 8 - 10 minutes. I smelled a burning smell. I was wearing jeans. When looking around to figure out where smell was coming from, my left leg came in contact with seat, I felt a "bite" sensation on the back of my leg - immediately I thought perhaps my seat was was on fire. I didn't see any actually flames, so I turned off seat heater, and opened the windows - hoping to cool off the interior of the car to prevent any smoldering in the seat to advance to a fire (sounds a stupid now, but at the time it seemed to make sense). Continue driving with one hand, windows down, and fanning seat with the other. With the windows down, the smoke/burning smell dissipated. By the time I got home (about another 10-15 minute drive from the initial occurrence), the seat had cooled. I observed a burn spot on driver's seat where I felt the "bite" on the back of my leg. I also thought my jeans were burnt; however, that turned out to be transfer from the burnt material from the seat - I was able to scratch most of it off with fingernail. Also, my skin was not injured. I will be contacting my local Mazda dealership today.