I have a 2004 blazer ZR2, and just got it really, noticed the temp on the overhead works fine, but has no direction on the compass, which isn't a big deal, but would be nice if it worked. Now, it says CAL on the reading, which I would assume means calibration, I have tried driving in a 360, 3 times and all that bull, and nothing has seemed to work. Any other things I can check or whatnot, thanks.

 

Ran a search for "CAL+compass" and came up with the following thread:
Question about compass and temp display on my 98 blazer