Chevrolet Repair Questions? Ask a Chevy Mechanic for Answers ASAP
Welcome, I'm Chris (aka Moose) I prefer to work when others don't, I am here around lunch and after dinner till after midnight.
At the top of this diagram https://dl.dropboxusercontent.com/u/90220402/99gmc.pdf check all the fuses involved. If they are all good then we need a diagnostic tool to check the module communication wires to see if the cluster itself is bad or if its not getting the signals sent to it.
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