Key Fob

Discussion in 'Gen 2 Prius Main Forum' started by artie, Jul 24, 2006.

  1. artie

    artie Member

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    my '04 is 2.5 years old. of late (the last 2 weeks) there have been a few failures for the smart entry to work and/or the keyless ignition to recognize the presence of the key in my pocket (the little logo shows on the screen indicating no key in the house), and then after repeat trying, both door and start will work.
    this has happened with both my key fobs, but only a few times at the door and only once with the start process.
    could the keys need batteries? has anyone had to replace batteries in their keys?
     
  2. marjam

    marjam Member

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    I have an '04 and yes, I replaced the batteries about a year ago. I had it done at the dealer but I believe there is a detailed explanation of how to do it yourself in the owner's manual.
     
  3. tumbleweed

    tumbleweed Senior Member

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    It is in fact in the owners manual and it is real easy to do. There is a little latch you push over to remove the mechanical key; you have to hold it over to get the back cover off also. Under the back cover are 4 very small phillips screws, take them out and you will be where the battery is. Get the O ring back in right or it won't be water proof any more.
     
  4. artie

    artie Member

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    i was at my toyota dealership today in san diego, the mgr. said that if the red light is working, the battery is ok. and that his store had rec'd. at least 20 reports in the last 2 week of fobs not working, his thinking is that it may be the heat (all time hot and humid in once cool by the sea san diego), and that toyota was investigating.
    sounds possible, but many of you are in arizona, and other deserts, with real heat, and i haven't heard of abnormalities re SES as yet.
    my gut feeling is that the batteries start to go after 2.5 years. he did say that some of the reports of malfunction come from new or newer prii.
    hmmm. i wonder what to do.
     
  5. mssmith95

    mssmith95 Michael

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    <div class='quotetop'>QUOTE(artie @ Jul 28 2006, 05:18 PM) [snapback]294070[/snapback]</div>

    Like usual they are full of it!

    The LED takes a minute amount of voltage to function. It has nothing to do with the actual functioning of the remote. I have installed hundreds of car alarms, and thousands of remote batteries. Almost always the LED still functioned when the remote did not.

    Change the batteries. In fact, I would change them yearly, just to prevent this type of issue down the road. And as far as heat...yes it can have an effect...but a lot of us keep our keyes in our pockets...and it is pretty hot and humid in a pocket!
     
  6. Bill Merchant

    Bill Merchant absit invidia

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    I agree with Mike. The fob battery is cheap and the procedure is simple, compared to the hassle of not being able to open the door or start your car. Change your fob battery regularly. Based on the evidence, every year.
     
  7. Mr. Tuco

    Mr. Tuco New Member

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    Well, I accidentally dropped the key fob in the water and still works perfectly. The thing must be water proof.
     
  8. Bill Merchant

    Bill Merchant absit invidia

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    <div class='quotetop'>QUOTE(Mr. Tuco @ Jul 29 2006, 02:36 AM) [snapback]294247[/snapback]</div>
    One guy reported leaving his fob in his pants pocket and sending it through the clothes washer (by mistake) and having no problems. Waterproof, yes, infinite battery life, no.
     
  9. Sufferin' Prius Envy

    Sufferin' Prius Envy Platinum Member

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    <div class='quotetop'>QUOTE(mssmith95 @ Jul 28 2006, 09:48 PM) [snapback]294183[/snapback]</div>
    Do we have to decipher what “it” is? :huh:

    I agree with the dealer - therefor I believe the “it” refers to them being full of knowledge. :p :lol:

    The little red light – ON THE KEY FOB ITSELF (located to the right of the lock button) – will only flash when the key is properly interrogated by the car and proper signals are sent back and forth. If you don't believe this, take both of your key fobs in one hand with the LED lights facing you, then walk up to the front driver or passenger door. Only one key will flash. The other key remains silent, dumb – whatever.

    If, on the other hand, you push one of the buttons on the key fob, the LED will flash if a proper signal is being sent – within range of the car or not. It is the key fob's electronics which tell the LED light to flash, not just the voltage level of the battery. If you have a weak battery, a proper signal may/could still be generated, but your range will be greatly diminished.

    Another reason the car may not respond to the fob could be interference from another electromagnetic source, such as your cell phone, a nearby TV, radio, or radar antenna, or high-voltage transmission lines.

    The Owner's Manual devotes several pages to the Smart Key. Read up! You may learn something new like I did . . . I didn't know that the Smart Key System will disable itself if the system does not receive a signal from the key for more than 14 days, or, if the key is left outside of the car, but within effective communication range for more than 10 minutes. :eek:

    By all means, CHANGE THE BATTERY! It probably is weak after 2.5 years . . . but rest assured, you will never be stranded because of a dead key battery. Use the mechanical key to open the door, then place the key fob in the slot to start the car.
     
  10. artie

    artie Member

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    i replaced both batteries in the fobs over 3 weeks ago. working fine.

    tonite...not working unless i keep trying and trying and touching and re-touching the door handle, and then it works most of the time. the fob works if i push the button on the fob, the lite lites, but the door button and door handle are not reacting. there is no outside interference that i can sense, unless the martians are here, and i don't know what else to do??? :(
     
  11. Cheapskate919

    Cheapskate919 Junior Member

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    I know I'm pretty late to the post (what's a decade?), but I've been arguing with both of the fobs for our '04 Prius. Changed both batteries, made sure accessory battery putting out appropriate power, made sure button under steering wheel in the right spot. Still nothing. Pressed the batteries further into the cavity and then hit a button and FINALLY got the red light on the fob. I ended up cutting 1/2" or so of toothpick and putting it on the back of the battery so the lid would push the battery far enough to function properly. Both fobs fixed.
     
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