Cant use headlights and combo meter at the same time

Discussion in 'Gen 2 Prius Technical Discussion' started by Braydon Stewart, Mar 19, 2022.

Tags:
  1. Braydon Stewart

    Braydon Stewart New Member

    Joined:
    Mar 19, 2022
    1
    0
    0
    Location:
    Surprise, Arizona
    Vehicle:
    2004 Prius
    Model:
    II
    I recently changed the 12v battery in the back, so i know this isnt just due to the battery dying, but whenever i turn on the headlights the screen starts to glitch and display the “lexus” logo and the combo meter completely shuts off, except seatbelt, door, and turn signals all still work. The speedometer and odometer do not, however.
     
    #1 Braydon Stewart, Mar 19, 2022
  2. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    25,966
    16,948
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    I would first make sure the panel dimmer is turned all the way up, just to eliminate the possibility that the combo meter is just going dark because the marker lights are on.

    Beyond that, it would just be a matter of using a voltmeter to measure on some key circuits when the headlights are turned on, working from the wiring diagram (more info) to see if there is an excessive voltage drop somewhere, and correcting that.

    You might be able to get some information to start off with, just using the voltmeter built into the "signal check" screen of the MFD.
     
    #2 ChapmanF, Mar 19, 2022
  3. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    111,568
    50,804
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    lexus logo?
     
    #3 bisco, Mar 19, 2022
  4. prius_chatter

    prius_chatter Junior Member

    Joined:
    Oct 25, 2020
    20
    9
    0
    Location:
    Montreal
    Vehicle:
    2007 Prius
    Model:
    N/A
    #4 prius_chatter, Mar 19, 2022
    bisco likes this.
  5. Another

    Another Senior Member

    Joined:
    Jun 22, 2021
    1,817
    515
    0
    Location:
    Naples, Florida
    Vehicle:
    2007 Prius
    Model:
    Touring
    It’s subliminal suggestion engineered by the same Toyota guy who designed in some of the more annoying features of the Prius.
    It’s aim is to get the owner not a mindset to upgrade to a Lexus after a fixable MFD fails.
     
    #5 Another, Mar 20, 2022
(You must log in or sign up to post here.)