Power button light

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by MM Butler, Dec 11, 2025 at 10:24 AM.

  1. MM Butler

    MM Butler New Member

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    Could have sworn that the power button light should be green! The other day it was red, car started up fine and drove. Someone told me to replace the battery in the key fob. I did. Now the light is amber! I start the car with foot on brake, press the power button, light is amber then goes out. Ready light is on dashboard, car drives. Looked at some online info - could be 12v battery, could be hybrid, it also could be fine!! 12v was checked - 12.02 before starting car. 14.2 when started. Need to know if it's a big deal because it does run.
     
    #1 MM Butler, Dec 11, 2025 at 10:24 AM
  2. Tombukt2

    Tombukt2 Senior Member

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    12 .2 is starting to take a dump .car is smart
     
    #2 Tombukt2, Dec 12, 2025 at 5:22 AM
  3. dolj

    dolj Senior Member

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    No, it isn't, 12.02V is a long way off the 10.5V mentioned in the repair manual, and it really depends on the actual fault that is reported to know if voltage is a factor.
     
    #3 dolj, Dec 12, 2025 at 6:48 AM
  4. MM Butler

    MM Butler New Member

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    Got a new battery. Amber light came on power button and went out. Ready light is on dashboard. Car drives.

    I read that 12.2 was low for battery with no load. Replaced battery. Amber light came on when pressing button. Went out. Ready light on dashboard. Car started and drove.
     
    #4 MM Butler, Dec 12, 2025 at 7:08 AM
    Last edited by a moderator: Dec 12, 2025 at 11:15 AM
  5. Hayslayer

    Hayslayer Active Member

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    Indicator
    Power Switch B080592E01

    Power Switch Mode Indicator Status
    OFF OFF
    ON (ACC) Green illumination
    ON (IG) Amber illumination
    Hybrid System ON OFF

    Push button start system malfunctioning Flashes continuously in amber
     
    #5 Hayslayer, Dec 12, 2025 at 7:12 AM
    Tombukt2 and Brian1954 like this.
  6. MM Butler

    MM Butler New Member

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    I always thought the light on power button was green? Doing some internet searches and it's saying it shouldn't be amber. So you're saying that amber is ok?
     
    #6 MM Butler, Dec 12, 2025 at 8:12 AM
  7. Tombukt2

    Tombukt2 Senior Member

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    Check your 12 volt 30 minutes after you shut the car off with dvom at batt if possible or at jump point if ya must
     
    #7 Tombukt2, Dec 12, 2025 at 9:12 AM
  8. Hayslayer

    Hayslayer Active Member

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    Just showing what the repair manual chart shows for normal operation:

    If the power switch is OFF, the indicator is OFF
    If the car is in ACC mode, the indicator is Green (one press of power button with foot NOT on brake)
    If the car is in IG-ON mode, the indicator is Amber (two presses of power button with foot NOT on brake)
    If the Hybrid system is ON, the indicator is OFF (one press of power button with foot ON brake)
    If the push button start system is malfunctioning, the indicator will flash amber continuously.
     
    #8 Hayslayer, Dec 12, 2025 at 12:49 PM
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