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Main display won't turn on when started

Discussion in 'Gen 2 Prius Technical Discussion' started by Canton Steve, Apr 15, 2022.

  1. Canton Steve

    Canton Steve New Member

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    About once a month, when I start my '07 Prius, the car will run okay, but the main display won't light up. Also, the center display doesn't show any information related to mileage. Sometimes I can just restart it and it's okay, other times, it won't correct itself after several attempts.
     
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  2. Tombukt2

    Tombukt2 Senior Member

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    Yep mine too for years . But at some point it comes back on . So seemingly not the dreaded display caps. Or? If I don't unplug anything when it comes back on my mileage is still correct it's been logging even while the display is off my gas tank will come up to where my brain thinks it should be from where i've been because i'm weird like that and when it comes on it's exactly that way so i've just left it the display guy down in texas seems to think there's a connection everything needs to be taken apart cleaned electrically greased and put back together etc that's a lot of plugs. I'll also got all the brake lights on but the pedal works fine and the ABS pump assembly doesn't seem to be pumping itself to death i've left it too when I can't push the brakes and stop anymore then the car goes out of service or we attempt to fix it
     
  3. bisco

    bisco cookie crumbler

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    prius-combination-meter-repair
     
  4. ChapmanF

    ChapmanF Senior Member

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    Sounds exactly like the dreaded display caps.
     
  5. priusrecon

    priusrecon Member

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    I've had that for a few years now. It comes and goes, sometimes only working half the time in the summer, usually not a problem in the winter.

    I bought and installed a scan guage which will display my speedometer readings from the ALDL port whenever it is not working.

    I don't usually sweat it until inspection time rolls around. If it fails me then, I'll deal with it.

    Other than that, it's easy to live with.
     
  6. bisco

    bisco cookie crumbler

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    ?
     
  7. mr_guy_mann

    mr_guy_mann Senior Member

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    If that works for you, then fine.

    When mine went out, none of the warning lights on the dash would work, and not having a fuel gauge kinda stunk- so I fixed it asap. And the whole inspection thing as well.

    Posted via the PriusChat mobile app.
     
  8. T1 Terry

    T1 Terry Active Member

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    Our Taxi Prius has this illness, sometimes turning the headlights on and the blinker before pressing the brake pedal and the start button will get it to work again, but only after it has sat all night. Short stop/start trips where the car is turned off and locked generally results in no speedo etc the next time we start it up .... a pain in the butt, the odometer doesn't add the distance covered while the screen is blank, so the taxi Prius has a lot more than the 740,000km shown on the odometer .... one day I'll get around to pulling the whole dash out and fixing it ..... if I can't convince the wife she can do it after watching the you tube videos on the subject :lol:

    T1 Terry
     
  9. Canton Steve

    Canton Steve New Member

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    How do I know if it's the combination meter or the power to it? I don't want to go through all the work to change it out, then find out it's the connection or power supply.
     
  10. mr_guy_mann

    mr_guy_mann Senior Member

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    First you can look at the wiring diagram in the service manual to locate which fuses supply power to the Combination Meter- then test them.

    Also, if you begin disassembly and dismount the dash panel above the steering column that has the power button (maybe 10-15 minutes of work)- underneath the panel are two connectors that have all the circuits that go to the CM. Using the wiring diagram, you can test all the power feeds and grounds at those connectors.

    Posted via the PriusChat mobile app.
     
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  11. bisco

    bisco cookie crumbler

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    ^^^agree^^^ you will have to start with 12v health, and work your way all the way to the meter. a lot of work either way.