Front Defrost HVAC & Code 43

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by natenkiki2004, Feb 9, 2021.

  1. natenkiki2004

    natenkiki2004 New Member

    Joined:
    Feb 9, 2021
    2
    0
    0
    Location:
    Washington
    Vehicle:
    2008 Prius
    Model:
    Two
    Hi all. I got a used 2008 Prius a few weeks back and am really enjoying it. However, I noticed that the front defrost wasn't working well, having to drive with fog on the inside of the windshield. Even with the AC on and set to front defrost, it takes a long time, a good 20 minutes before it clears. I ran the diagnostic function and got code 43 on the display, relating to the servo motor. Looking under the dash, I can see and hear the upper servo moving but something is still wrong, it doesn't seem to move fully the other direction to allow air out the top of the dash by the windshield. I have floor and vent air, just nothing out of the very top.

    Can anyone provide insight on what steps I should take going forward? This is all still new to me. Thanks.
     
    #1 natenkiki2004, Feb 9, 2021
  2. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    11,725
    8,458
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    Your code, a/k/a B1443, indicates that the car's HVAC controller did not see the position-sensor signal change as it was trying to move the air outlet select servo, so that's consistent with your symptoms.

    The position sensors in those Gen 1 and Gen 2 servos are a known trouble spot, and not hard to clean (if that turns out to be the issue). Here is a thread with information on that. I think the outlet select in Gen 2 is the higher of two servos visible on the left side of the heater case, no? It may be rather more difficult to remove than the temperature blend servo below it.
    Working on a Gen 2, yitznewton found a specialty thin offset screwdriver useful, mentioned in post #13 of the thread linked above.

    It is also possible that something has mechanically broken or jammed, but getting to the servo is probably the first step of investigation in any case.
     
    #2 ChapmanF, Feb 10, 2021
    SFO likes this.
  3. natenkiki2004

    natenkiki2004 New Member

    Joined:
    Feb 9, 2021
    2
    0
    0
    Location:
    Washington
    Vehicle:
    2008 Prius
    Model:
    Two
    Thanks for the link to that thread. I'm getting a handle on how to get up there and pull those out. I was messing around and unplugged the lower one. Naturally, I have more codes now. I went to read the codes in a cheap OBD2 scanner and there's no body/HVAC codes listed. Is there any way to clear those codes aside from disconnecting the battery? I'm wondering if I clear the code, maybe the servo will try to move again and can limp me through winter since I don't have a garage.
     
    #3 natenkiki2004, Feb 10, 2021
  4. pasadena_commut

    pasadena_commut Member

    Joined:
    May 2, 2019
    272
    84
    0
    Location:
    Southern California
    Vehicle:
    2007 Prius
    Model:
    N/A
    This probably isn't your issue, but just in case, have a quick read through it. Bottom line, earlier AC work on my car resulted in a botched reassembly where they neglected to reattach some plugs to their sockets, with one of them giving the 43 error code. They also forgot to reattach the TPMS.

    No air out of defrost vents at windshield | PriusChat
     
    #4 pasadena_commut, Feb 11, 2021
(You must log in or sign up to post here.)
Loading...
Similar Threads - Front Defrost HVAC
  1. rm04

    Front and rear brake job on 2004 gen 2?

    rm04, Apr 12, 2021 at 10:47 PM, in forum: Gen 2 Prius Care, Maintenance and Troubleshooting
    Replies:
    6
    Views:
    539
    bisco
    Apr 13, 2021 at 7:16 PM
  2. diave

    Front and rear defrosters come on by themselves

    diave, Jun 11, 2020, in forum: Gen 2 Prius Care, Maintenance and Troubleshooting
    Replies:
    1
    Views:
    311
    dolj
    Jun 11, 2020
  3. SFPriusonr

    Front defroster causes red triangle of death

    SFPriusonr, Jan 18, 2018, in forum: Gen 2 Prius Care, Maintenance and Troubleshooting
    Replies:
    8
    Views:
    1,276
    SFPriusonr
    Feb 16, 2018
  4. royalbulldog

    Front defroster cutting off

    royalbulldog, Jan 23, 2014, in forum: Gen 2 Prius Care, Maintenance and Troubleshooting
    Replies:
    1
    Views:
    735
    Patrick Wong
    Jan 24, 2014
  5. bobkat21

    front defrost

    bobkat21, Dec 9, 2005, in forum: Gen 2 Prius Care, Maintenance and Troubleshooting
    Replies:
    13
    Views:
    8,575
    adllewellyn
    Oct 16, 2009