Key Fob Power Drain

Discussion in 'Challenger DIY/Tech Info' started by SRT-Tom, Jan 23, 2020.

Car Parts
  1. SRT-Tom

    SRT-Tom Full Access Member Article Writer

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    Did you know that once your key fob is about 8 ft. away, it is out of the range of your car's antennas (there's several on the car) and the CANBUS* will go to "sleep mode" and not communicate with it? As a result, there will be no drain on the fob's battery.

    If, for some reason, you have to store your fob within this communication range (e.g., in your garage), place it is a metal cookie tin or Faraday pouch/case to prolong the life of its battery.

    Despite this precaution, after 3 years, it is a good idea to replace the fob battery. The following thread explains this simple process:

    https://www.challengerforum.com/thr...dge-challenger-key-fob-battery.476/#post-3223

    On a related engine battery matter, it's best to lock your car. This signals to the car's electronics that the car is not going to be used for a while and it can enter its lowest power mode sooner. Don't worry about the draw of the security system. It uses some power but it is not on all the time. It is switched on and then off every so often- every second or so- and it is on for just a real short time which reduces the power it consumes.



    *CANBUS stands for Controller Area Network bus. In the electrical sense, a 'bus' is a kind of connective hub that allows for communication between two or more circuits or components. A CANBUS is connected to - and so spots faults in many parts of a vehicle. For instance, low tire pressure may trigger an error message on the dashboard.
     
    Last edited: Jan 23, 2020
  2. IntimidatorRT

    IntimidatorRT Well-Known Member Staff Member Super Moderator

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    I take it that this pertains to the beginning year as of 2009 for our challengers? Technology has done advanced pretty good since then.


    Sent from my iPhone using Tapatalk
     
  3. SRT-Tom

    SRT-Tom Full Access Member Article Writer

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    No, this applies to all Challengers built since 2008.
     
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  4. Hopslayer

    Hopslayer Full Access Member

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    A few times I had my key fob in my coat pocket when working outside in below freezing temps. It wouldn't work until I put it in my shirt pocket and warmed it up.
     
  5. B5blueRT

    B5blueRT Full Access Member

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    My wife and daughter would freak out when they first got the message to replace the key fob battery in their car. They were worried it wouldn't work anymore, or die in an hour, at the end of the day or when. I got in the habit of replacing all six of our key fob batteries every year in the fall when we change our clocks... do the smoke detectors at the same time.
    Safe insurance and the 2032 batteries are cheap on Amazon.
     
  6. SRT-Tom

    SRT-Tom Full Access Member Article Writer

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