One problem related to turn signal switch has been reported for the 2006 Chevrolet Trailblazer. The most recently reported issues are listed below.
Left turn signal is intermittent. While switching lanes or in need to switch lanes the left turn signal might turn on then completely stop or won't turn on at all. The right turn signal works all the time. The left turn signal will work fine, then out of no where will stop working, then will start working fine. It does this whether the car is moving or stationary, on the highway, streets, or in my garage. The safety concern is when I need to turn it seems like I've changed my mind and might cause an accident.