Just bought a 2006 and there is knob sticking out of the display at the top right that you push in and it changes the display from the odometer to the trip meter. The information is apparently stored in the PCM and however their is a memory in the instrument cluster itself.
See answer for same question on 2004 Chevy avalanche. JIT
where is the O2 sensor on a 2002 chevy trailblazer
disconnect the battery
where is the temperture sensor located on a 2002 chevy trailblazer with a 4200 motor
I need a diagram for the vacuum lines on a 2004 Chevy trailblazer
How do you reset the computer in a 04 blazer 4.3L
You have to replace the cluster. Then the dealer must reprogram it with the appropriate mileage. You can find vendors on EBay. www.trailvoy.com Trailblazer enthusiasts forum
it is located in the fuel tank
its in the gas tank
Under the back seat
its on the tailshaft of the transmission
under each coil