When I come home, I usually put my key fob into my a faraday box to prevent thieves from scanning the remote and stealing my 2020 RDX.

I've discovered recently that keeping the key fob in the faraday box causes the key fob battery cell to drain after just a couple weeks.

I assume the key fob is trying to communicate with the RDX and since it's in the faraday box, the key fob keeps trying unsuccessfully thus draining the battery cell. I confirmed the issue using No 2 key fob with the same results. I further tested the problem by leaving the key fobs outside the faraday box and both remote no longer had cell draining issue after 1 month of usage.

Seems the faraday cage is great to prevent the key fob signal from being stolen by thieves, however, it is not so good in that it drains the key fob battery cell pretty quickly when it can't communicate withe the RDX...

Others having similar issues with the remote battery life shorten when placed inside a faraday box?

Maybe there is a way to turn OFF the remote (by key strokes) instead of using a faraday box?

Thanks for the help.

 

That's pretty annoying... have you tried removing the coin cell battery from the key fob before putting it in the faraday box?

 

Is there a chance the faraday box isn't working 100% and the key fob is in too close to the RDX? Have you tried to unlock and/or start the RDX with the fobs inside the faraday box in your hand?

 

A Faraday box should actually increase fob battery life, not decrease it to a level of just a few weeks as you describe. I would try a new set of batteries and make sure they are a brand name like Energizer or Duracell, not something acquired at a Dollar Store.

 

If you remove the battery, there isn’t any need for a Faraday cage.

 

The fob normally acts as a radio receiver. When you place your hand on the RDX's door handle, a radio signal is transmitted from an antenna in the door, for approximately a 3' radius of that door.

The fob receives the signal, and then it transmits it's unique code. If that code has been previously entered into the RDX'S computers, the door will unlock.

Transmitting requires much more power than recieving does. That can be seen everyday in our cell phones. Their batteries can last a full day, or longer when idle, but may only last a few hours when talking, especially in a rural area.

Sometimes electrical noise from things like fluorescent lights, TV's, etc., can cause the fob to transmit it's signal. That normally wouldn't be a security problem since it only transmits a short distance, and if the door handle isn't being touched at the time, the doors won't unlock.

Bottom line is that by shielding your fob from radio signals sent by the RDX or any other source, will prevent it from transmiting, and thus extend battery life. The opposite of what you are experiencing.

More than likely, your short battery life is caused by using discount batteries. I recommend only using Eveready Energizers for this type of battery. Also don't store your fob near any device that can cause radio interference.

 

Thanks for the info Rick. I've used fresh Duracell 2032 cell with 10 years expiration dates. I am keeping Remote No 1 in the cage and No 2 outside of it and will compare how both remote batteries last. Will update the thread in a few weeks time or earlier if No1 remote battery dies prematurely again. Attached is the faraday box I am using.

 

Looks like a coffin for it

 

Is that box 100% all metal; sides, top and bottom? Otherwise it isn't a Faraday cage. Easy way to check, as someone suggested earlier, is carry the box with fob in it to the locked car and see if the car unlocks using the buttons on the handle.

 

Yes it is John, tested by the car and totally shields the key fobs signals.

 

Another thing since you are using Duracell batteries. They are coated with something bitter to prevent kids from putting them in their mouth and thus reduce swallowing. There are people reporting that the coating causes short battery life. The coating can be removed with rubbing alcohol, a pencil eraser, emory cloth, etc. Energizer by the way does not have the coating.