Question about 1999 GMC Jimmy

2 Answers

My 1999 gmc jimmy heater is stuck on heater mode every time, no matter what i do. Please help.

Posted by on

Ad

2 Answers

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

    President:

    An expert whose answer got voted for 500 times.

  • GMC Master
  • 1,348 Answers

There is either a linkage that connects to the control box knob,or vacuum lines .If the linkage is off or the knob is broken,it will not switch modes,and if the vacuum controlled actuator has an issue. Remove the trim plate,then remove the control panel by removing the 4 screws,take a look behind it to see if it is broken.

Posted on Dec 30, 2010

Ad
  • Level 1:

    An expert who has achieved level 1.

    Corporal:

    An expert that has over 10 points.

    Mayor:

    An expert whose answer got voted for 2 times.

    Problem Solver:

    An expert who has answered 5 questions.

  • Contributor
  • 18 Answers

Your control switch is most likely malfunctioning. You will need to replace it. If you are a do-it-yourselfer you can order a used part online from a scrap yard; see eBay Auto. If not, go to your local dealer for replacement. Hope this helps.

Posted on Dec 30, 2010

Ad

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of.(from cars to computers, handyman, and even drones)
click here to download the app (for users in the US for now) and get all the help you need.
Goodluck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%

my-video-file.mp4

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

×

Loading...
Loading...

Related Questions:

1 Answer

1999 gmc jimmy cant get heat, heater core fine, can get heat on floor but nothing when switch to vent. can see actuators working. ambient temp sensors resistance on 1 one passenger side no resistance


just went through the same thing in my 99 silverado.could see acctuators working also,but i still had to change" mode" acctuator as it was only operating on 2 modes not all 5

Nov 19, 2016 | GMC Cars & Trucks

2 Answers

1999 gmc jimmy heater runs hot when turned all the way up but runs cold if turned down even a little ?


will be this heater mixer valve its vacuum operated

could be a vacuum leak or faulty valve

26316790-lxjlcmzd5vobdfbwpupduwwl-3-0.jpg

26316790-lxjlcmzd5vobdfbwpupduwwl-3-1.jpg

Oct 18, 2016 | 1999 GMC Jimmy

1 Answer

There is hot air coming out of vents at all times in my 1998 jimmy


Sounds like you have a bad heater door actuator.

May 31, 2014 | 1998 GMC Jimmy

1 Answer

Where is shift actuator located on 1999 Jimmy 1999


I had the same problem with my 1999 Silverado which would blink several times on the mode I selected then go back to the 2 wheel High. I found the switch module to be defective, after replacing it I have never had the problem again.

Nov 22, 2010 | 1999 GMC Jimmy

2 Answers

I have a 1999 Jimmy, the heater just blows cold air ownly, temp. knob works but somthin is stuck, the AC work great, but I need heat, where should I be lookin, to make it work right? I live on the west...


Sounds like the heater cor is plugged. I belive yours is under the hood. Look for a set of 3/4 inch heater hoses going into the firewall. Remove the output hose(bottom)and start the engine to see if water comes out of the heater core. If it does, it is a stuck blend door inside the duct work of the heater, which is under the passenger side dash

Sep 25, 2010 | 1999 GMC Jimmy

1 Answer

Heating Unit problem


check the fuse and the wires.

Jun 19, 2010 | 1999 GMC Jimmy

1 Answer

1999 gmc jimmy. The heater control is stuck on HOT.


if the knob wont move replace it junk yard may have used part but if it moves and hot air keeps blowing out u may need a servo that opens and closes heater box door under dash i dont think that trucks system works off vacuum but if it does it probably electronic related problem inquire junk/salvage yard about knob and servo for heater box door and problem it may be common and u may get info if he,s a nice guy

Mar 28, 2009 | 1999 GMC Jimmy

2 Answers

Heater temp control not working


We had the same problem in our 98 GMC Jimmy. Was blowing hot air everywher with everything shut off & air conditioning would not work. We found out it was the Blend Dood Actuator, it is located behind the glovebox. We purchased one on EBay & replaced it and are back on track again. Good luck!

Dec 13, 2008 | 1998 GMC Jimmy

1 Answer

1994 GMC Jimmy stuck in 4-wheel low.


Have you tried this: put it in nuetral and push on the brake! Then as your doing these things push the 2 wd button!

Dec 06, 2008 | 1998 GMC Jimmy

Not finding what you are looking for?
1999 GMC Jimmy Logo

226 people viewed this question

Ask a Question

Usually answered in minutes!

Top GMC Experts

yadayada
yadayada

Level 3 Expert

76673 Answers

Freddy

Level 3 Expert

1311 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22219 Answers

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

Answer questions

Manuals & User Guides

Loading...