1. Attachments are working again! Check out this thread for more details and to report any other bugs.

No cabin heat unless "HI"

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by bwilson4web, Apr 11, 2016.

  1. bwilson4web

    bwilson4web BMW i3 and Model 3

    Joined:
    Nov 25, 2005
    27,397
    15,522
    0
    Location:
    Huntsville AL
    Vehicle:
    2018 Tesla Model 3
    Model:
    Prime Plus


    A coolish morning, the sun warmed cabin felt nice when I got in. But soon down the road, the chill started to come in. No problem, turn on the heater fan and it was already set to 74, a toasty place to be . . . nothing but cool air. I increased the temperature setting . . . nothing but cool air. Eventually I set it on "HI" and warmth returned. But soon as I lowered the temperature, it soon cooled off.

    Current hypothesis:
    1. Make sure radiator coolant level in overflow tank and radiator is OK.
    2. MiniVCI check for any codes or problems.
    3. Check 12V battery (still original but marginal batteries can cause all sorts of 'funnies')
    4. Check cabin heater coolant circuit for blown fuse
    Any other thoughts or suggestions?

    Bob Wilson
     
    #1 bwilson4web, Apr 11, 2016
  2. qdllc

    qdllc Senior Member

    Joined:
    Aug 25, 2013
    1,370
    399
    0
    Vehicle:
    2013 Prius
    Model:
    Two
    Thermal sensor telling the A/C the cabin temp is faulty?
     
    #2 qdllc, Apr 11, 2016
  3. Dennis_MA

    Dennis_MA Active Member

    Joined:
    Jul 20, 2012
    185
    109
    0
    Location:
    Amherst, MA
    Vehicle:
    Other Electric Vehicle
    Model:
    N/A
    Cabin air filter?
     
    #3 Dennis_MA, Apr 11, 2016
  4. xliderider

    xliderider Senior Member

    Joined:
    Apr 19, 2012
    7,869
    3,116
    0
    Location:
    Honolulu, HI
    Vehicle:
    2011 Prius
    Model:
    Three
    Is the fan operation normal in AC and non AC modes? It's common for resistors in the blower motor control to fail, commonly causing loss of certain speeds while leaving other speeds unaffected.
     
    #4 xliderider, Apr 11, 2016
  5. RRxing

    RRxing Senior Member

    Joined:
    Jul 7, 2009
    2,520
    1,791
    0
    Location:
    NEPA
    Vehicle:
    Other Hybrid
    Model:
    Limited
    Thermostat?
     
    #5 RRxing, Apr 11, 2016
  6. bwilson4web

    bwilson4web BMW i3 and Model 3

    Joined:
    Nov 25, 2005
    27,397
    15,522
    0
    Location:
    Huntsville AL
    Vehicle:
    2018 Tesla Model 3
    Model:
    Prime Plus
    Fan is OK. Will check filter but that does not explain symptom.

    Bob Wilson
     
    #6 bwilson4web, Apr 11, 2016
  7. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    108,894
    49,482
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    air in the system?
     
    #7 bisco, Apr 11, 2016
  8. bwilson4web

    bwilson4web BMW i3 and Model 3

    Joined:
    Nov 25, 2005
    27,397
    15,522
    0
    Location:
    Huntsville AL
    Vehicle:
    2018 Tesla Model 3
    Model:
    Prime Plus
    That is the coolant level issue. I got home about 4 hours ago so it should be cool enough but it is drizzling outside.

    The radar shows about 4-6 more hours so I'll go out later. I'm home, warm and dry . . . keep it that way.

    Bob Wilson
     
    #8 bwilson4web, Apr 11, 2016
  9. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    108,894
    49,482
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    bourbon and water.
     
    #9 bisco, Apr 11, 2016
    Rebound likes this.
  10. CR94

    CR94 Senior Member

    Joined:
    Dec 2, 2014
    2,642
    1,137
    0
    Location:
    Northwestern S.C.
    Vehicle:
    2011 Prius
    Model:
    Two
    That's more plausible than most of other guesses so far. A related possibility is an open circuit in wiring to that sensor.
     
    #10 CR94, Apr 11, 2016
(You must log in or sign up to post here.)