My heater air cold when turn my heater

SOURCE: The rear heater does not generate heat - only cold air in vents

does front air work properly? for heat i mean?.. the blend doors are suspect as well as the heater hoses to the rear core and its heater valve.. possibily the control head is to blame or?, but i cant tell from here

SOURCE: 2002 GMC Yukon blows cold air from the front, rear works fine

check you antifreeze level and make sure its full

SOURCE: Faulty Fan Heater - The main vents are just blowing out cold air.

Go to your idrive., climate the vent settings. you will see a person along with vent areas on the side.
If this persons color is blue it blows cold air so turn the dial for vent closest to that person until the
color changes red then hot air comes out on the vents for driver and passenger. Then let me know.

Mark
2006 BMW 530i sport

SOURCE: 2000 gmc sierra 1500 5.3 v8. a/c heater control problem

your heat/cool and vent selection options are controlled by engine vacuum through small clear tubes attached to the rear of your climate control interface. Other vehicles have small steel pull wires that operate the desired changes. You might try removing the trim and any fasteners affiliated with the interface/console. GENTLY pull outward and look to see if any of these tubes are pulled off or cut/damaged. Did anyone recently install a new stereo in the vehicle? If so, the vacuum tubing and or pull wires that change your outlets could have been damaged when the stereo unit was pushed into place. Hope this helps

Testimonial: "Very good information. THANKS!"

Marvin

• 85242 Answers
• Posted on Oct 06, 2010

SOURCE: when I turn on the heater cold air comes out the

there is a part inside the dash that controls the outlet air temperature by moving back and forth between the heater core and the AC evaporator core, it is called the Blend door, the door is moved by a small electric gear drive that is called the blend door actuator motor, very likely this motor has failed or the bend door is stuck due to warping (it is a light weight plastic), the bad news here is that the entire dash assembly must be removed to replace these parts, I am a Ford dealer tech so I have seen this problem dozens of times.

Testimonial: "I appreciate your help. I'm an 85 yr old who used do almost all the repairs on cars. But this is sort of out of my ability now that I'm gettig on in"