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Help - Immobilizer System

Discussion in 'Gen 3 Prius Main Forum' started by NEPrius1, Jul 25, 2009.

  1. NEPrius1

    NEPrius1 Junior Member

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    My 2010 Prius is still new to me but I dont think I saw this happen until this evening.

    As I was getting out of my car this evening, the immobilizer light began to flash (see page 108 of owners manual regarding the light). I dont think I ever saw this light flashing before and wonder if it is something normal. I just put the car in park, set the parking brake, powered down the vehicle and it started flashing. If I lock the doors with the key fob, it keeps flashing. Unlock the doors, still flashing! Only when I power the car back on does it stop flashing.

    Is this normal? Does everyone else have a flashing immobilizer light?

    The only thing that I did different tonight than I have done since owning the car (about one week) is use a TomTom.

    Any advice would be greatly appreciated.
     
  2. jay_man2

    jay_man2 jay_man_also

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    Page 108 of the Owner's Manual tells me that the light flashes when the car's powered off to indicate that the system is operating properly.

    You can register on Toyota.com on the Owner's page and get searchable access to the Owner's manuals.
     
  3. ziporder

    ziporder Junior Member

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    Mine does the same thing. According to page 108 its normal. I think I just didn't notice it for a couple of weeks.
     
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  4. NEPrius1

    NEPrius1 Junior Member

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    I have reread page 108 of the manual and it appears that this is normal. However, when I first saw this flashing, I read the manual but very honestly, I just did not remember this happening in the past. Again, I have been driving the car for only a week, so I must have missed this feature. Glad that it is normal.

    If the flashing is normal, wouldn't this drain down the battery over a long period of time ( i.e. a couple of weeks) when the car is parked. For example, I travel a lot for work and at times, leave my car parked at the airport parking lot for long periods.
     
  5. jay_man2

    jay_man2 jay_man_also

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    I only recently noticed the flashing, but didn't give it a second thought as the last several Toyotas I've owned had some sort of security alarm or immobilizer flash when powered off.

    I can't comment on the battery drain except to say there are other threads here that discuss battery drain and the smart key system, and how the Gen II has a switch to turn off the smart key antenna, and the Gen III doesn't.
     
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  6. wave_slider

    wave_slider New Member

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    All Toyota's have a flashing red light somewhere on the dash. It indicates that the vehicle has engine immobilizer and can also appear to be an alarm to some. Any vehicle's immobilizer light will begin flashing when the key is removed from the ignition.

    Gen III's don't have a slot to put a key in and flash when the vehicle is turned off. Perfectly normal.
     
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  7. jim256

    jim256 Member

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    But it does turn itself off:

    "In the following circumstances, the entry function is disabled in order to pre-vent the vehicle battery from discharging and electronic key battery from depleting.
    [FONT=Times New Roman,Times New Roman][FONT=Times New Roman,Times New Roman]l [/FONT][/FONT]When the entry function has not been used for 5 days or more
    [FONT=Times New Roman,Times New Roman][FONT=Times New Roman,Times New Roman]l [/FONT][/FONT]When the electronic key has been left within approximately 6 ft. (2 m) of the vehicle for 10 minutes or more
    [FONT=Times New Roman,Times New Roman][FONT=Times New Roman,Times New Roman]l [/FONT][/FONT]If the entry function has not been used for 9 days or more, the vehicle cannot be unlocked by a door other than the driver’s door. To unlock the vehicle, grip the driver’s door handle or use the wireless remote control or the mechanical key."
     
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  8. David Beale

    David Beale Senior Member

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    The LED draws about 15 mA when on. If it's on for 0.5 sec every two seconds that's an average current of 3.75 mA. The battery has a capacity of over 30 A-Hrs. It could provide 3.75 mA for 4000 hrs to half capacity. That's 167 days. Now, the immobilizer system does draw more than that, but not a lot more.

    Be aware there are other systems in the car that also draw power constantly. Then there are systems that run "in the night" (what was that bump?). ;) These run intermittently. If you sit in the car with the power off, but with the FOB (SKS equipped car), the car will draw power to "get ready for you to run it".

    Yes, eventually the battery will go dead. No, it won't happen "in a few weeks", unless you already have a bad battery. I'd guesstimate 6-10 weeks with a healthy battery. Prius is not the only car that will drain the battery "just sitting". Almost any newer model car will do this.
     
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  9. cunningpaul

    cunningpaul New Member

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    I realize this string is over a year old but I was wondering if this issue is a common one for Gen III owners with a smart key? I purchased my car close to a month ago and never once saw this blinking red light turn on until tonight. I had looked up the info on pg. 108 of the owner's manual and deduced the same as was posted in this string. However, I find it odd that this so-called "normal" feature took a month to kick in. I am 100% positive this light never turned on before now (and my wife who drives the car too never noticed it either). Not sure what's changed.
     
  10. OklahomaPrius

    OklahomaPrius Junior Member

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    I also agree I have had my Gen II for a month and the Light never flashed until today after I washed the car. There has to be something else. Anyone have an update?
     
  11. David Beale

    David Beale Senior Member

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    Take a course in observation. ;)

    The light flashed from day one. You were just blinded by the beauty of the car.
     
  12. Charlie Clyne

    Charlie Clyne New Member

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    Your answer is absolutely wrong! I brought my 09 Prius brand new and now have almost 55,000 miles on it. It has been driven many times by multiple family members.

    The red light, in the shape of a car, with a key inside it has never, never ever been illuminated until last week.

    The previous posts are correct.
     
  13. David Beale

    David Beale Senior Member

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    A light also will come on when the FOB battery is getting weak. If you think this is different than normal operation change the battery and see if it changes the light action. There ARE two lights.
    The Prius flashes a red light about once every 5 sec. or so when off. This they do from new.
    The second light is only used when there is something wrong with the system (FOB weak signal, etc.).
     
  14. jabecker

    jabecker driver of Prii since 2005

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    Agree with David. They all do it. My 2005 did and my 2012 did. But the light only flashes when the car is off. It's easy to miss, because how often do you sit around in your car when it's turned off?
     
  15. Lola Brigida

    Lola Brigida New Member

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    I noticed mine tonight after having it for 3 weeks. I RTFMed. Then I found this website. Maybe I was blinded by the beauty of the car. I just never noticed it until now. I like my new car overall. I hope it survives the New England winters.
     
  16. dbhope64

    dbhope64 New Member

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    I've had my 2012 PriuaV for two months now. There has positivly been no flashing red key on the dash until tonight. I noticed it because the overhead lights were on and I went to check it. I had to manually turn off the lights that usually dim after I leave the car. I will replace the key fob battery. That makes the most sense in this tread. I am very observant and know for sure this is a new event.