Question about 1998 GMC Jimmy

2 Answers

Blows hot all the time.

The a/c works but the air doesn't get to the cabin. The car blows hot as if the heater is on. Someone mentiond the blend door. Any help fixing this problem?

Posted by on

  • 1 more comment 
  • Anonymous Jul 09, 2008

    I have the same problem. The blend door actuator gear was broken and now it only spins in one direction and doesn't stop. Put in a new actuator and it goes all the way to one side.

  • GMCrocks Jul 09, 2008

    I have the same problem. I removed the blend door actuator and found that the big gear that turns the door was broken. I left it uncovered to see that it simply turns in one direction when the key is turned on. I tried a new actuator and it did the same thing. Don't know what to do. I also tried removing the RDO/BATT fuse and touching the battery terminals together for one minute. However, one interesting thing is that before the a/c issues, if I took the battery out, I had to enter a code for the radio. Now, for some reason, I can leave the battery unhooked all night and I don't have to enter the code and all of my stations are still in memory. Weird.

  • chastity027 Sep 18, 2008

    My car blows out hot air... at our feet

×

2 Answers

  • Level 1:

    An expert who has achieved level 1.

    Habit-Forming:

    Visited the website for 3 consecutive days.

    Welcome Back:

    Visited the website for 2 consecutive days.

  • Contributor
  • 2 Answers

I fixed the problem. It was the blend door actuator, but the wheels continued to turn because the reset operation requires resistance to know when the blend door is at its limit for the hot and cold side. At least that is what I assume. If the actuator is tested off of the blend door, it will simply turn until it can't turn anymore. After installation, it worked fine.

Posted on Sep 25, 2008

  • Level 1:

    An expert who has achieved level 1.

    Hot-Shot:

    An expert who has answered 20 questions.

    Corporal:

    An expert that hasĀ over 10 points.

    Problem Solver:

    An expert who has answered 5 questions.

  • Contributor
  • 21 Answers

Dont know what it is but there should be a reset procedure for that it works like a tps 0 volts for cold and 5 volts for hot give or take

Posted on Sep 24, 2008

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

2 Answers

Heater not blowing hot air in cabin


Check the coolant level. Check for leaks. Next would be clogged heater core(doubt that 2004) next would be the water pump. Kind of doubt that also, 2004. But if you have leaks?

Dec 25, 2014 | 2004 Chevrolet TrailBlazer

1 Answer

The heater kicks on but only blows cold air


Air Temperature Control Blend Door Failure No Heat or no AC (dependes on where door sticks)

In all modern cars there is a tiny DC electric motor driven gear drive that moves a plastic door that blends heated and cooled air from the AC and the heater core, this is called (interestedly enough) the air temperature control blend door actuator. The motor that moves this door fails because the door starts sticking from warping, most common complaint is no heat but it can be no AC as well. To replace these parts (blend door and blend door actuator) you must remove the entire dash from the car. Always have this problem confirmed by a dealer or qualified repair shop as it is a very expensive repair.

Other causes of no heat in the cabin are engine thermostats that are stuck open (engine runs cold) or air bubbles in the cooling system.

Jan 03, 2013 | Cars & Trucks

1 Answer

Heater not working


HEATER NOT BLOWING COLD,NO HOT AIR FROM HEATER,A/C BLOWS HOT AIR,A/C NOT BLOWING COLD, COLD AIR FROM HEATER,BLEND DOOR ACUTATOR CLOSED,HVAC UNIT NOT OPERATING,
http://alltypesofpartsreplacing.blogspot.com/2012/12/heater-not-blowing-coldno-hot-air-from.html

Dec 26, 2012 | 2001 Ford Taurus

2 Answers

Heater doesn't get hot on 96 chevy truck. Blows good, just cold. Replaced thermostat, flushed radiator. Any ideas?


Air Temperature Control Blend Door Failure No Heat or no AC (dependes on where door sticks)

In all modern cars there is a tiny DC electric motor driven gear drive that moves a plastic door that blends heated and cooled air from the AC and the heater core, this is called (interestedly enough) the air temperature control blend door actuator. The motor that moves this door fails because the door starts sticking from warping, most common complaint is no heat but it can be no AC as well. To replace these parts (blend door and blend door actuator) you must remove the entire dash from the car. Always have this problem confirmed by a dealer or qualified repair shop as it is a very expensive repair.

Other causes of no heat in the cabin are engine thermostats that are stuck open (engine runs cold) or air bubbles in the cooling system.

Dec 06, 2012 | Cars & Trucks

2 Answers

1997 astro van blows only lukewarm air?


sounds like your blend door is stuck in the middle of the operating range. this door directs air either fully or partially over the heater core or ac evaporator. when stuck in the middle u will alwaysd get a blend of both

Nov 17, 2012 | 1998 Chevrolet Astro

1 Answer

1997 chevy silverado blows hot air only through vents


If you know for a fact the compressor is running and one of the lines is cold, I would look for a blend door problem. The blend doors direct air thru the heater and evaporator.

Aug 31, 2012 | 1999 Chevrolet Silverado 1500

2 Answers

Heater blows cold air, replaced thermostat &


try to back flush the heater core. and if that dont work check the blend door it see if it is working.

Oct 15, 2009 | 2002 Mitsubishi Galant

1 Answer

98 XJ cherokee sport 4.0 a/c blows hot air not warm, hot like the heater will not disengage. ac is charged lines and canister are cold. all positions on selector blows heater.


check that the heater control valve on the heater hoses is working, also check that blend door inside heater box and blend door vacuum motor are working. Likely the problem is with the door or motor, but unfortunately, the entire heater box needs to be removed to get to them on most vehicles.

Jul 11, 2009 | 1998 Jeep Cherokee

1 Answer

Lincoln navigator front heater cool


this is caused by the main cabin temp blend door actuator motor, in order to replace it or even check it the dash must be pulled out.

Dec 15, 2008 | 2003 Lincoln Navigator

Not finding what you are looking for?
1998 GMC Jimmy Logo

835 people viewed this question

Ask a Question

Usually answered in minutes!

Top GMC Experts

yadayada
yadayada

Level 3 Expert

60960 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

21949 Answers

Jeff Turcotte
Jeff Turcotte

Level 3 Expert

6812 Answers

Are you a GMC Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...