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Hidden key fob features?

Discussion in 'Fred's House of Pancakes' started by cyberpriusII, Aug 17, 2019.

  1. cyberpriusII

    cyberpriusII Prodigyplace says I'm Super Kris

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    Your Car's Key Fob May Have Hidden Features - Consumer Reports

    never heard about the above before. A quick Google did not indicate any such features for a Gen 2...but are there any?

    Also did not find any for a 2019 Subaru Outback.

    But, then again, did not search too hard.

    Basically, I found the "hidden features" story while trying to figure out if I keep two key fobs next to each other in a bowl is good, bad or indifferent (a co-worker said it was bad -- considering I have been doing just that with my two Prius fobs for a decade, I figure he's wrong -- and my 2019 Outback fob joined the party in April.)

    Hmm, also found a warning not to keep fobs near any house access point (windows/doors) as thieves are apparently capturing the signal from outside, boosting it and opening/starting cars and driving away...
     
    #1 cyberpriusII, Aug 17, 2019
    Last edited: Aug 17, 2019
  2. bisco

    bisco cookie crumbler

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    gen 4 may have one or two

    all our fobs are in the same cabinet with no ill effects. about 12 feet from the cars and we get 4 or 5 battery years typically.
     
  3. The Electric Me

    The Electric Me Go Speed Go!

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    I guess I've been lucky with my Key Fob. Both Prius and Honda Fit. Both with keyless entry and push button start.
    I accidentally put my Honda Key Fob through the wash, and a dryer, and no damage....and it looked cleaner.- Not advising it...I got lucky.

    Most of those revealed "secret features" I've read about. But I'm pretty sure my Fit doesn't have them. So I'm not too worried about accidentally triggering them.

    The only thing I do, on some ghost advice which I can't even remember where I originally got ( I'm getting old ). Was I have my Fob, and the spare, which I keep separate. BUT....somewhere I heard that when you replace the battery in the one you use, you should go ahead and replace the battery in the spare too.

    I think the premise was that with keyless entry, even the unused fob can be transmitting a signal. Therefore, the battery can weaken even though it's not in daily use.

    So anyway, it's cheap insurance. When I need to replace the battery in my operational, daily use fob, I buy two batteries and replace (and test) both fobs.

    With the Fit....3 years...one battery replacement...1 wash cycle, 1 tumble dry, and NO problem yet.
     
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  4. Trollbait

    Trollbait It's a D&D thing

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    Our Sable's fob spent a year or so in the mud of the driveway. Just cleaned it off and replaced the battery, and the only sign of its adventure was a scuffed case.

    All batteries self discharge to some degree, and being in use could speed that up. The Camry was about a year old when we got it. I assume the fob batteries are original. When one got weak, I just switched fobs. It isn't a critical safety device for the car, so I don't have an issue waiting for the battery to die.

    Weak signal would be more of nuisance with a smart key fob. I'd get the spare battery at time to replace the primary, but not install it until needed. I think you can turn of the smart key function of some fobs off to preserve the battery's charge.
     
  5. The Electric Me

    The Electric Me Go Speed Go!

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    Well, like a lot of voluntary maintenance expenditures, I often balance possible benefit vs. cost.
    For me? These batteries often come in 2 packs, so the cost is minimal. Also, if I'm going to sit down and replace the battery? Might as well do both at the same time, at a time when it's NOT an emergency situation.
    I think the worst outcome is losing my original in use fob, only to dig out my spare and find it not working because the battery has gone dead.
    Also batteries can leak, become corroded. Opening up the fob, replacing the battery, on a regular cycle, dictated by the usage of the original fob, seems reasonable to me.
     
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  6. Fastfret7

    Fastfret7 Junior Member

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    Oh man.... I was hoping there were some. D'oh!
     
  7. Trollbait

    Trollbait It's a D&D thing

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    It's not like needing a flashlight in the middle of the night during a power outage. You can still get into and drive the car with a dead battery in the fob. It won't risk potential safety issues like replacing just one worn tire on an axle. Sure, it isn't convenient, but convenience probably went out the door with the missing primary fob.

    I know the batteries are cheap, and changing them on a fob isn't as easy as for the TV remote, but I see changing them early as a waste of resources. Some may still contain toxins like mercury to dealt with. I put this in the same category as changing the oil early.

    I don't recall ever coming across a leaking button battery, but if that is a concern for a seldom used device, the best thing to do is to leave the batteries out. That is actually the recommendation for an emergency flashlight; leave the batteries out, and store them together.

    As for OT, these 'hidden' features are likely listed in the owner's manual. The Camry one had them there, but they seem to only be on the higher trims.:(
     
  8. The Electric Me

    The Electric Me Go Speed Go!

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    No, it's more like needing your fob, if you've lost your primary fob and potentially finding the back-up fob non-functional because the battery is dead.

    Hey, do what you want to do. BUT.....
    Like I said in my original post, I can't even remember where I heard this advice now. But the contention was that the unused fob was discharging even while not being used.
    It may not be the most environmentally advantageous choice...true. BUT...eventually you're changing the battery anyway. Dispose of both the discarded batteries properly and I think I can rest with my conscious clear.

    My fob seems to last about 1 -2 years per battery replacement.
    My choice is changing BOTH batteries in both fobs is my choice.
    My bottom line, is I think changing the batteries..both of them is a good idea.
     
  9. Tideland Prius

    Tideland Prius Moderator of the North
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    Not for Gen 2 (other than putting the fob near the POWER button to start in case of low battery power in the fob).

    The Gen 4 does have the lower windows feature but it’s off by default. You have to turn it on at the dealer.
     
  10. Trollbait

    Trollbait It's a D&D thing

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    Dead flashlight, and you stumble around in the dark. Dead fob, you pull out the back up key to unlock the car door, and hold the fob near the the power button to start the car. If the car became useless with a dead fob, that is an extremely poor design choice.

    The battery is discharging in the spare fob, but it isn't near the rate of the one being used. The fob I'm using now was the one that sat in the drawer for at least a year, and the battery is still good a year of use later.
     
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  11. The Electric Me

    The Electric Me Go Speed Go!

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    Feel free to not change both at the same time.
    I think it's a good idea.
     
  12. Trollbait

    Trollbait It's a D&D thing

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    I was just trying say that I think your source has over estimated how quickly the spare fob battery is draining.

    Personally, I'll probably end up changing both at the same time, but I switched which one I use when the primary started showing signs of a weak battery. Though I may be mistaken on how weak it is, because the Sonic's fob had a greater range than the Camry's.