# No A/C or Heat or Fan air

**URL:** <https://community.cartalk.com/t/no-a-c-or-heat-or-fan-air/1009>\
**Category:** Maintenance/Repairs\
**Tags:** gmc\
**Created:** [June 27, 2007, 1:35am UTC](https://community.cartalk.com/t/no-a-c-or-heat-or-fan-air/1009 "2007-06-27T01:35:55Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![ramileez](https://avatars.discourse-cdn.com/v4/letter/r/47e85d/32.png) [@ramileez](https://community.cartalk.com/u/ramileez)\
**Post date:** [June 27, 2007, 1:35am UTC](https://community.cartalk.com/t/no-a-c-or-heat-or-fan-air/1009/1 "2007-06-27T01:35:55Z")

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I have a 93 GMC Sierra pickup 4.3 liter 6cyl 1500 long bed. Occasionally my fan would stop working and I’d have to reach down under the passenger side and give it a good whack and then it would start working again. Well about six months ago, it did it again but this time the “Whack” didn’t work so in my frustration, I whacked just above the controls on my dash and it all stopped working. No fan, no a/c, no heat, no display. I checked all the fuses and even removed the whole control module and checked for 12 volts at the plug. Thinking that I may have damaged the control module, I purchased a used one, and installed it to no avail. HELP!!!

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**Author:** ![star882](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/star882/32/39_2.png) [@star882](https://community.cartalk.com/u/star882)\
**Post date:** [June 27, 2007, 3:58am UTC](https://community.cartalk.com/t/no-a-c-or-heat-or-fan-air/1009/2 "2007-06-27T03:58:05Z")

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Most likely a bad connection somewhere. Or the motor was just about to fail and it finally burned out.

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**Author:** ![Cougar](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/cougar/32/21348_2.png) [@Cougar](https://community.cartalk.com/u/Cougar)\
**Post date:** [June 27, 2007, 5:53am UTC](https://community.cartalk.com/t/no-a-c-or-heat-or-fan-air/1009/3 "2007-06-27T05:53:58Z")

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It sounds like there is a bad power connection somewhere. Check your fuses also. If you can’t find the problem by moving wire connections around I suggest you get a service manual and trace the power to the panel using a test light probe to check for power.

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**Author:** ![Tester](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/tester/32/15976_2.png) [@Tester](https://community.cartalk.com/u/Tester)\
**Post date:** [June 27, 2007, 2:15pm UTC](https://community.cartalk.com/t/no-a-c-or-heat-or-fan-air/1009/4 "2007-06-27T14:15:41Z")

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[b]That’s the classic symtom of a worn out blower motor.

Replace the blower motor and the vent system will work again.

Tester[/b]

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**Author:** ![ramileez](https://avatars.discourse-cdn.com/v4/letter/r/47e85d/32.png) [@ramileez](https://community.cartalk.com/u/ramileez)\
**Post date:** [June 27, 2007, 11:04pm UTC](https://community.cartalk.com/t/no-a-c-or-heat-or-fan-air/1009/5 "2007-06-27T23:04:57Z")

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Thanks for the info but my display panel is totally black. No digital readout at all.

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**Author:** ![Beadsandbeads](https://avatars.discourse-cdn.com/v4/letter/b/c57346/32.png) [@Beadsandbeads](https://community.cartalk.com/u/Beadsandbeads)\
**Post date:** [June 28, 2007, 11:32pm UTC](https://community.cartalk.com/t/no-a-c-or-heat-or-fan-air/1009/6 "2007-06-28T23:32:23Z")

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A bad motor can draw too much current for the controls and blow them out after an extended period. It can heat stuff up chronically without blowing the fuse.