If your Buick has  the Dual Automatic ComforTemp 
Climate  Control  option, 
it looks like this: 
Ext Temp 
I 
EXT. 
The  following  information tells  you  how it works. 
You will hear a  beep each time  a  button is  pushed.  The 
display  will show  fan,  temperature  and mode settings.  Push this and 
the  display will indicate  the  outside 
temperature  (Unless 
the system is OFF). Push  it again to 
return  to the  regular  system display. 
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