Passenger door sensor no longer working

Discussion in 'Prius v Main Forum' started by wstt, Mar 1, 2019.

  1. wstt

    wstt Member

    Joined:
    Jul 11, 2013
    104
    7
    0
    Vehicle:
    2012 Prius v wagon
    Model:
    Five
    Has anyone ever experienced the passenger door sensor, which allows the door to be locked or unlocked if the key is in close proximity, stopping from working? Anyone have any ideas what could cause this and how to fix it?
     
  2. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    85,340
    37,600
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    Does the lock motor work?
     
  3. Air_Boss

    Air_Boss Senior Member

    Joined:
    Jun 2, 2012
    2,931
    688
    0
    Location:
    New Yawk
    Vehicle:
    2012 Prius v wagon
    Model:
    Five
    Failing keyfob battery?
     
  4. rjparker

    rjparker Senior Member

    Joined:
    Jun 6, 2008
    1,845
    697
    1
    Location:
    Texas Hill Country
    Vehicle:
    2012 Prius v wagon
    Model:
    Three
    There is a module in the door handle itself that detects your hand or the antenna that picks up the fob for that side of the car. Typically the car will illuminate some interior lights as you approach which may be a way to determine if the antenna is at fault. I would change the battery in the fob as it may be just strong enough for the drivers and starting but perhaps not for the passenger side. I suspect the Techstream software through OBD2 may show some status as well. It's hard to troubleshoot Toyota specific ecus without that tool. There may be some settings in the headunit that could impact it as well. Maybe a lockout. Attached is a drawing of the antenna circuits for what its worth. antenna.jpg
     
    Air_Boss likes this.
  5. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    85,340
    37,600
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    low 12v?
     
    Air_Boss likes this.
  6. wstt

    wstt Member

    Joined:
    Jul 11, 2013
    104
    7
    0
    Vehicle:
    2012 Prius v wagon
    Model:
    Five
    The door does lock and unlock with the fob. I’ve also Replaced the battery on the fob.
    I’ll try they antenna test one night to see if interior lights light up as I get close.
    I also wonder if there is a fuse for it somewhere.
     
  7. Air_Boss

    Air_Boss Senior Member

    Joined:
    Jun 2, 2012
    2,931
    688
    0
    Location:
    New Yawk
    Vehicle:
    2012 Prius v wagon
    Model:
    Five
    Coincidentally, my key fob just turned up dead, won't lock or unlock doors, while the SO's fob works just fine. Off to find a fresh CR1632...
     
  8. mikefocke

    mikefocke Prius v Three 2012, Avalon 2011

    Joined:
    Nov 3, 2012
    2,669
    1,097
    0
    Location:
    Sanford, NC
    Vehicle:
    2012 Prius v wagon
    Model:
    Three
    Wasn't the nearness of the keyfob unlocking effect a function of some configuration setting in some models? I seem to recall this being a feature on one of the upper end models and since the OP has a Five...
     
  9. Air_Boss

    Air_Boss Senior Member

    Joined:
    Jun 2, 2012
    2,931
    688
    0
    Location:
    New Yawk
    Vehicle:
    2012 Prius v wagon
    Model:
    Five
    We have a five and a dead fob doesn't work, close or far...
     
  10. rjparker

    rjparker Senior Member

    Joined:
    Jun 6, 2008
    1,845
    697
    1
    Location:
    Texas Hill Country
    Vehicle:
    2012 Prius v wagon
    Model:
    Three
    You can remotely lock or unlock with the fob much further away than the proximity antenna detects your presence and illuminates the interior (and I would assume, enables the door handle open feature).
     
  11. Air_Boss

    Air_Boss Senior Member

    Joined:
    Jun 2, 2012
    2,931
    688
    0
    Location:
    New Yawk
    Vehicle:
    2012 Prius v wagon
    Model:
    Five
    That's been our experience, as long as the fob battery works. With a dead battery, there is no proximity detection, so it is not purely a passive transponder. THAT was a surprise.
     
  12. wstt

    wstt Member

    Joined:
    Jul 11, 2013
    104
    7
    0
    Vehicle:
    2012 Prius v wagon
    Model:
    Five
    I tested the interior light illuminating as I approached the car and noticed the lights do not come in when approaching the passenger door, but do on the driver side. That makes it sound like it is the antenna as you implied it might be. Is there maybe a fuse that powers the unlocking / locking through the door handle and the antenna sensing the key near?
     
  13. rjparker

    rjparker Senior Member

    Joined:
    Jun 6, 2008
    1,845
    697
    1
    Location:
    Texas Hill Country
    Vehicle:
    2012 Prius v wagon
    Model:
    Three
    If the driver's side works, it is unlikely a fuse is bad as both doors feeds the same "certification ecu". Looking at the drawing, it appears the door handle assembly itself may have an antenna which means the handle "could" be bad. However I would check the configuration settings in the head unit (p 523 of owners manual) and verify there is not a simple setting fix.

    Again, the Toyota Techstream ODB2 system would help by monitoring those devices.

    Detailed troubleshooting procedures are available on the Toyota TIS information system (techinfo.toyota.com), which is accessible online (twenty dollars for two days) with download capabilities of the information. Unfortunately, it's not "one" big manual but hundreds of separate docs which are linked together when you are online. Plus one can easily get overwhelmed trying to find things without knowing terms and names. Having a dealer diagnose the problem could be worth the money.

    Reading the schematics only goes so far on a highly software driven system where logic sequencing is everything. Attached are two more drawings, one shows the certification ecu's 7.5 amp fuses, the second shows the door handle module.
     

    Attached Files:

    #13 rjparker, Mar 19, 2019
    Last edited: Mar 19, 2019
    Raytheeagle likes this.
  14. Landon51

    Landon51 Member

    Joined:
    Apr 18, 2018
    153
    56
    0
    Location:
    US
    Vehicle:
    2007 Prius
    Model:
    Two
    I have a gen 2 w sks. My only master fob just suddenly wit working. The buttons don't cause a lock unlock j And, if i touch the handle, nothing. It will start the car.

    My initial reaction was, " Fuuuuuu...dge." After thinking about it some. I'm considering doing the chicken dance with just that one key. The computer should still have the numbers in the fob so it will probably allow me to create an identical record of a second activated let fob. That is assuming that qa didn't text that condition.

    Posted via the PriusChat mobile app.
     
Loading...