A couple years ago I took my Aztek in to get an oil change. The next day as I was driving I notice my speed display was not working, assuming it was due to the fact that the garage had trouble resetting the computer after the oil change to clear the display. Of course the shop denied any wrong doing and told me it would cost $100+ to takeout a mother board and send it to Texas and I would have to relinquish my vehicle for several days while it was looked at. At that time if it was deemed to be defected then they could replace it at the tune of $400+ extra! So I use my GPS to keep up with how fast I'm driving! Sincerely; Watching out for the PO-PO!