Hi,
My trailblazer 2009 model Temperature gauge is zero and Ac not getting on frequently.Randomly it becomes OK and back again with the same trouble.Can you please share you experience to get rid of this issue.

 

to clarify: are you referring to the engine coolant temp gauge or ambient air temp reading?

 

Please note if the Temperature gauge is for the engine and if your AC was not cooling properly prior to the problem you have then you can just remove the battery connection on your battery and reconnect after about a minute.

This will solve the problem for time being. If still the problem exists please go on to change the Thermo Stat Valve. the same i did face about a week ago.
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