If the tach and speedo were dead also, it could be a communication failure elsewhere that stopped messages from getting to the cluster. Yours sounds like an internal death.
Enay has repair vendors to look at such things. Run a search for "trailblazer gauge repair" and email them with your symptoms. Could be a $100 fix instead of $800 from the dealer.
Enay has repair vendors to look at such things. Run a search for "trailblazer gauge repair" and email them with your symptoms. Could be a $100 fix instead of $800 from the dealer.