# Auto A/C question. **URL:** \ **Category:** In My Humble Opinion\ **Created:** [February 26, 2008, 12:52am UTC](https://boards.straightdope.com/t/auto-a-c-question/439161 "2008-02-26T00:52:33Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![A.R.Cane](https://avatars.discourse-cdn.com/v4/letter/a/ee7513/32.png) [@A.R.Cane](https://boards.straightdope.com/u/A.R.Cane)\ **Post date:** [February 26, 2008, 12:52am UTC](https://boards.straightdope.com/t/auto-a-c-question/439161/1 "2008-02-26T00:52:33Z")
My A/C compressor is cycling on/of about every 40-50 seconds. the dash control is set fot heat. It’s a '96 Cherokee. I’m going to take it to a shop, but I’d like to know probable causes so I can try to avoid getting skinned. BTW, I put my hand on the back of the unit and can feel it immediately get colder when it kicks in, so I’m sure it’s the compressor. ---
**Author:** ![KneadToKnow](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kneadtoknow/32/3999_2.png) [@KneadToKnow](https://boards.straightdope.com/u/KneadToKnow)\ **Post date:** [February 26, 2008, 1:05am UTC](https://boards.straightdope.com/t/auto-a-c-question/439161/2 "2008-02-26T01:05:38Z")
Is the defroster on? ---
**Author:** ![A.R.Cane](https://avatars.discourse-cdn.com/v4/letter/a/ee7513/32.png) [@A.R.Cane](https://boards.straightdope.com/u/A.R.Cane)\ **Post date:** [February 26, 2008, 1:14am UTC](https://boards.straightdope.com/t/auto-a-c-question/439161/3 "2008-02-26T01:14:19Z")
You know, it might have been. I’ll have to run it again, making sure the defrost is off, and repost. Thanks. ---
**Author:** ![Joey\_P](https://avatars.discourse-cdn.com/v4/letter/j/919ad9/32.png) [@Joey\_P](https://boards.straightdope.com/u/Joey_P)\ **Post date:** [February 26, 2008, 4:46am UTC](https://boards.straightdope.com/t/auto-a-c-question/439161/4 "2008-02-26T04:46:18Z")
Even if the defroster is on, I don’t _think_ it’s supposed to cycle like that. It could be low on freon.