I just bought a used 1992 GMC extended cab truck and when I try to turn on the A/C all the text "A/C" appears in the LED display area and starts blinking. The compressor never kicks in and the blinking A/C text does not go away until you turn the key off and back on. Does anyone know what this means? I'm guessing the A/C might need to be recharged or something but I've never seen this symptom on any of the GM's I've seen.

 

its low of freon...you'll have to disconnect the battery to clear it before you begin putting freon in