Lane Departure Assist setting grayed out

Discussion in 'Prime Main Forum (2017-Current)' started by bb4srv, Nov 13, 2020.

  1. bb4srv

    bb4srv Active Member

    Joined:
    Mar 5, 2018
    138
    101
    1
    Location:
    Canada
    Vehicle:
    2018 Prius Prime
    Model:
    Technology
  2. Tideland Prius

    Tideland Prius Moderator of the North
    Staff Member

    Joined:
    Oct 2, 2004
    42,071
    13,634
    41
    Location:
    Canada
    Vehicle:
    2018 Prius Prime
    Model:
    Technology
    Did you enable it by pressing the LDA button on the steering wheel? (the one with the vehicle diagonal to the direction of travel on the right hand side of the wheel)
     
  3. Gokhan

    Gokhan Active Member

    Joined:
    Oct 5, 2008
    975
    451
    0
    Location:
    Paramount CA
    Vehicle:
    2021 Prius Prime
    Model:
    Limited
    What?? The auxiliary battery is never meant to be disconnected. That's your problem there. Now, you need to take the car to the dealer to have the steering-angle neutral point and back-door lock initialized.

    INITIALIZATION

    PROCEDURES NECESSARY WHEN AUXILIARY BATTERY TERMINAL IS DISCONNECTED/RECONNECTED

    NECESSARY PROCEDURE: Memorize steering angle neutral point

    EFFECT/INOPERATIVE FUNCTION WHEN NECESSARY PROCEDURES NOT PERFORMED:

    --------
    Lane departure alert system (w/ Steering Control)
    Intelligent clearance sonar system*1
    Simple advanced parking guidance system*1
    Pre-collision system
    --------

    NECESSARY PROCEDURE: Initialize back door lock

    EFFECT/INOPERATIVE FUNCTION WHEN NECESSARY PROCEDURES NOT PERFORMED:

    --------
    Power door lock control system
    --------

    *1: When performing learning using the Techstream.

    NOTICE: After the power switch is turned off, the radio and display receiver assembly records various types of memory and settings. As a result, after turning the power switch off, make sure to wait at least 85 seconds before disconnecting the cable from the negative (-) auxiliary battery terminal. (for Audio and Visual System) After the power switch is turned off, the navigation receiver assembly records various types of memory and settings. As a result, after turning the power switch off, make sure to wait at least 120 seconds before disconnecting the cable from the negative (-) auxiliary battery terminal. (for Navigation System) When the cable has been disconnected and reconnected to the negative (-) auxiliary battery terminal, open and close the fuel lid before turning the power switch on (IG).

    HINT: The accuracy of the fuel receive gauge changes depending on fuel tank deformation caused by internal pressure. Before turning the power switch on (IG), equalizing the fuel tank pressure with the ambient air pressure by opening and closing the fuel lid after disconnecting and reconnecting the cable to the negative (-) auxiliary battery terminal increases the accuracy of the fuel receiver gauge.
     
  4. bb4srv

    bb4srv Active Member

    Joined:
    Mar 5, 2018
    138
    101
    1
    Location:
    Canada
    Vehicle:
    2018 Prius Prime
    Model:
    Technology
    I feel so foolish! Yes, indeed the steering wheel button was pressed and it disabled the feature. I pressed it again it it's available now.
     
    fotomoto and Tideland Prius like this.
  5. Washingtonian

    Washingtonian Active Member

    Joined:
    May 26, 2017
    562
    489
    0
    Location:
    Western Washington
    Vehicle:
    2017 Prius Prime
    Model:
    Plug-in Advanced
    I am not sure what Gokhan is talking about. The 12V battery is not called an auxiliary battery. There is nothing in the owner's manual that that it should not be disconnected other than that the ignition switch should be off first. What the Hell is the "steering angle neutral point"? Back door lock??? There are two back doors and a back hatch. What is he talking about initializing a back door lock? Today is Friday the 13th, not April 1st.
     
    bb4srv likes this.
  6. bb4srv

    bb4srv Active Member

    Joined:
    Mar 5, 2018
    138
    101
    1
    Location:
    Canada
    Vehicle:
    2018 Prius Prime
    Model:
    Technology
    I had my 12v previously ran dry b/c I forgot to battery tender during the March lockdown. It's not as devastated as the manual made it to be. Not saying you should try it, but it doesn't require ANY of those procedures upon disconnect/reconnect 12v.

    The ONLY thing I had to manually set was the time and calendar. I also re-did the TPMS just to be sure. All the sonar, radar, etc. will recalibrate itself after a short drive. I mean short, like less than 100 meters. I didn't even have to recalibrate the windows.

    As a side note: plugging in the traction battery charger DOES NOT charge the 12v. Just FYI. For storage, you need to also plug a battery tenderer for the 12v.
     
  7. Tideland Prius

    Tideland Prius Moderator of the North
    Staff Member

    Joined:
    Oct 2, 2004
    42,071
    13,634
    41
    Location:
    Canada
    Vehicle:
    2018 Prius Prime
    Model:
    Technology
    It is in some parts of the world so he's not wrong calling it an auxiliary battery.

    Also, "back door" is Toyota speak for hatch.

    Phew. Glad it was a simple solution.
     
  8. Gokhan

    Gokhan Active Member

    Joined:
    Oct 5, 2008
    975
    451
    0
    Location:
    Paramount CA
    Vehicle:
    2021 Prius Prime
    Model:
    Limited
    The 12 V battery is officially called the auxiliary battery by Toyota in all parts of the world. What I posted is copied and pasted from the official Toyota repair manual.

    I probably don't have the sections of the manual where the two initialization procedures (for steering and back-door lock) are discussed.
     
  9. Washingtonian

    Washingtonian Active Member

    Joined:
    May 26, 2017
    562
    489
    0
    Location:
    Western Washington
    Vehicle:
    2017 Prius Prime
    Model:
    Plug-in Advanced
    OK, I can accept that even though that is not what my 800+ page owner's manual calls it. What I cannot accept is your statement that if you disconnect it you must then go to the dealer to "memorize your steering angle input" or initialize the lock on the rear hatch. I can just imagine driving to my local Toyota dealer after I have cleaned the 12V battery terminals and asking them to memorize my steering angle input for me.
     
  10. Gokhan

    Gokhan Active Member

    Joined:
    Oct 5, 2008
    975
    451
    0
    Location:
    Paramount CA
    Vehicle:
    2021 Prius Prime
    Model:
    Limited
    It is not in the 800+-page owner's manual but it is in the 800+-thousand-page repair manual.

    I didn't download every section out of tens of thousands of sections, but Toyota doesn't put something in its repair manual unless it is significant. You can subscribe to TIS for a day for about $15 and download the relevant sections for the calibration procedure mentioned along with anything else of interest.
     
    #10 Gokhan, Nov 14, 2020
    Last edited: Nov 14, 2020
  11. Salamander_King

    Salamander_King Senior Member

    Joined:
    Nov 8, 2015
    7,805
    6,259
    0
    Location:
    New England
    Vehicle:
    2020 Prius Prime
    Model:
    LE
    While I am aware of the initialization necessary after the 12v battery disconnect, the "Memorize steering angle neutral point" and "Initialize back door lock" are new ones I have not read or heard. The manual does not list them either. Does it really need to be done every time the 12v battery is disconnected? My feeling is that in very rare cases removal of the 12v battery can cause problems in a system that may necessitate such a procedure. It would be crazy if a normal DIYer can not even change the 12v battery without a visit to a dealer. Then again, it is Toyota... maybe that's the way this car is designed.:(

    upload_2020-11-15_8-34-25.png
    BTW, the owner's manual for the 2020 PRIME (and presumably for earlier model years as well) does have the term "auxiliary battery". One twice in the same section, but still...
    Screenshot 2020-11-15 at 8.50.54 AM.png
     
    #11 Salamander_King, Nov 15, 2020
    Last edited: Nov 15, 2020
  12. bb4srv

    bb4srv Active Member

    Joined:
    Mar 5, 2018
    138
    101
    1
    Location:
    Canada
    Vehicle:
    2018 Prius Prime
    Model:
    Technology
    I can confirm again, ALL I needed to set after disconnecting and reconnecting the 12v are: TIME (calendar also pops up but if you did it the same day, then it's the same date). All other settings remains the same.

    You will get the S-AGPS unavailable message, but the sonar and radar will re-calibrate itself after you drive, within 1 mile/1km if you want to be specific.
     
    Tideland Prius likes this.
  13. Gokhan

    Gokhan Active Member

    Joined:
    Oct 5, 2008
    975
    451
    0
    Location:
    Paramount CA
    Vehicle:
    2021 Prius Prime
    Model:
    Limited
    I don't have the relevant section of the Toyota Prius Prime OEM repair manual on this, but I've found some information for some Lexus models.

    DIY LS430 Steering Wheel Centering/ ZERO STEERING ANGLE POINT - ClubLexus - Lexus Forum Discussion

    5) What is Steering Angle Neutral Point?

    The steering angle neutral point tells ECM that, according to the driver, the steering wheel in current position will be used for straight driving.

    ECM understands when the driver attempts to balance the straight driving during driving, however, it never resets this neutral point as it may create a serious safety condition.

    The only exception is when electronics enters learning mode and slightly corrects the VSC behavior to ensure the neutral point remains the same during straight driving. Once the behavior is learnt, it is saved in memory.

    If any steering pull is present, it may indicate faulty steering neutral point. However, during very low speed driving, the driver may notice the wheel is centered.

    5) How do I obtain Steering Angle Neutral Point?

    Lexus service manuals specifies that LS430 enters SYSTEM INITIALIZING mode once the negative battery cable is disconnected for more than 2 seconds.


    Important tip: The steering wheel must be centered in advance before coming to a complete stop - to avoid discrepancy, do not center the wheel when the car is already stopped.

    During the SYSTEM INITIALIZING mode, the driver must correct the steering angle neutral point using either of the following methods:

    - Method 1. Turn the steering wheel to the right and left fully.
    - Method 2. Drive the vehicle at more than 20 km/h (12.43 mph) for more than 5 minutes on a straight road and with as little traffic congestion as possible.

    While driving at a constant vehicle speed, the ECU recognizes the point where the steering angle changes the least and memorizes it as the steering angle neutral point.

    Stop the vehicle and check whether the neutral point is stored or not. If it is not stored, drive the vehicle some more (the neutral point is stored by driving the vehicle straight).

    6) Which method do I have to pick to reach the Steering Angle Neutral Point?

    Both. First method 1, then method 2.

    7) Does the discrepancy of 1,2,3,4 degrees of steering angle sensor cause car instability?

    Depends on your car suspension setup / age / mileage. Despite LS430 advanced VSC system, the driver may not even be aware of this condition. This explains why in many times wheel alignment in reputable shop cause such a great comfort. Whenever the systems are in perfect balance, it removes the necessity of additional brake actuator force applied during regular driving, which decrease wandering, pull, hesitations, and unexplainable throttle changes.

    That's it for now. Thank you for reading this DIY. Hopefully it helps someone to fix their steering wheel issue. Also, if anyone has additional thoughts on the Steering Angle system, please share them. This topic is poorly covered by LS430 service manual.
     
    Henrik Helmers likes this.
Loading...