1997 GMC C1500 ac will not work on hi

1997 GMC C1500
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RAULMATA
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  • 1 POST
Air Conditioning problem
1997 GMC C1500 6 cyl Two Wheel Drive Automatic

the ac works on all speeds except hi. i turned the switch to hi and jumped it u hear the relay go click but it will not blow any air
Jul 3, 2009 at 3:14 PM
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BUDDYCRAIGG
  • ✓ASE Certified Mechanic
  • 2,262 POSTS
  • ASE Certified Mechanic
the high side gets its power from a red wire, that has a 50 amp fuse under the hood.

but that fuse powers a lot of other things too, and you would have noticed if it was out.

so check for power at the red wire in the plug for the relay,.

and if the relay clicks when the switch is being turned from high to low. then the relay has to be bad.
Jul 4, 2009 at 7:32 PM
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