AF: HVAC not coming out of the right vents | Allpar Forums
  1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

HVAC not coming out of the right vents

Discussion in 'Minivans · Pacifica' started by thedriver, Jan 17, 2015.

  1. thedriver

    thedriver Active Member

    Joined:
    Feb 10, 2006
    Messages:
    256
    Likes:
    16
    My HVAC will only blow out of the dash front and defrost positions at all times. Turning the knob makes no difference. I have done the recalibration, but it ends up with the RR defogger blinking. Next step?
     
  2. ImperialCrown

    ImperialCrown Moderator
    Level III Supporter

    Joined:
    Jun 8, 2008
    Messages:
    21,192
    Likes:
    4,392
    Is this a 2006 MTC system? Does the recal procedure change the air blowing out the floor, vent and defroster positions (mode door test)? Does it also change the air temperature (blend door test)?
    The 'self-test' given here: http://www.allpar.com/fix/codes-climate.html may not work on the newer RS minivans and a capable scan tool may be needed to get BCM/HVAC fault codes and run calibration/diagnostics.
    See SYSTEM DIAGNOSTICS starting on p. 20 of the Body Diagnostic Procedures manual:
    http://oskin.ru/pub/chrysler-dodge/manuals/Service Manuals/2005_RS_Caravan_Voyager/2005-RS-Body.pdf
    It may be a stuck door or servo/stepper motor or linkage. Does anything move on the drivers side of the HVAC housing when you select a different mode or do you hear any 'clicking'?
     
  3. thedriver

    thedriver Active Member

    Joined:
    Feb 10, 2006
    Messages:
    256
    Likes:
    16
    during the recalibration you can hear the doors moving. afterwards there is no change.
     
  4. ImperialCrown

    ImperialCrown Moderator
    Level III Supporter

    Joined:
    Jun 8, 2008
    Messages:
    21,192
    Likes:
    4,392
    Is this a 2006 dual-zone MTC system?
    Calibration can improve HVAC volume and temperature performance, but it usually doesn't 'fix' door actuation problems. The quickest diagnosis is by scan tool (DRB III or equivalent).
    It sounds like a mode/distribution door is stuck or an actuator (servo) is not moving.
    You should be able to watch the mode/distribution linkage move under the drivers side of the dash with the ignition on and by selecting floor, panel or defrost. Watch for what isn't moving.
    http://ww2.justanswer.com/uploads/dodgetech77/2012-04-01_022026_ns_ac_blend_door.gif
     
  5. Dave Z

    Dave Z It's me, Dave
    Staff Member Level III Supporter

    Joined:
    Jan 23, 2001
    Messages:
    34,940
    Likes:
    20,627
    Just as a quick anecdote… anyone else remember vacuum actuated doors? Slam on the gas and the vents would change, if you had a bad vacuum reservoir. I think a lot of them came out of the factory nonfunctional...
     
    Ray Green likes this.
  6. thedriver

    thedriver Active Member

    Joined:
    Feb 10, 2006
    Messages:
    256
    Likes:
    16
    single zone base model T and C.
     
  7. gusc

    gusc Member

    Joined:
    Dec 8, 2004
    Messages:
    517
    Likes:
    39
    My '94 pickup did this when rats ate the vac line for the system. All I had was defrost and panel in any mode.

    Don't think this applies to late models though.
     
  8. ka9yhd

    ka9yhd Well-Known Member

    Joined:
    Aug 17, 2013
    Messages:
    1,322
    Likes:
    275
    Default is defrost mode. Might be a vacuum leak.
     
  9. ImperialCrown

    ImperialCrown Moderator
    Level III Supporter

    Joined:
    Jun 8, 2008
    Messages:
    21,192
    Likes:
    4,392
    No vacuum actuators, these doors are all controlled by electrical stepper motors with door position feedback to the BCM.
     

Share This Page

Loading...
 We are not affiliated with FCA. We make no claims regarding validity or accuracy of information or advice. Copyright © VerticalScope Inc. All rights reserved.