What does (off ext ) mean when i turn my air off ? on 2005 GMC Envoy

When i push the off button that message comes on. Off EXT???

by in Aurora, IL on July 07, 2013
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2 answers 1 comment
ANSWER by , July 07, 2013
No owners manual?
COMMENT by , July 08, 2013
Yes I have one but cant find it any were in it. :-(
ANSWER by , July 08, 2013
call dealer for info