Bertone
Posts: 30
Joined: Wed Jan 22, 2020 9:37 am
Location: Madrid, Spain

Remote Key fob battery discharging problem w. Easy access

Fri Oct 09, 2020 8:31 am

Hi,

My car has the easy access option, I.e. no need to press the key fob open button to open up the car. Just have the key in my pocket and the car gives me access.

This is all ok, if it were not for the constant need to replace the small battery in the key fob every 2 months or so.

Obviously the key is constantly checking if it is near the car, etc..and will drain much faster than a non easy access key..but I think that it should last longer.. When I park the car in my garage, I keep the key in a tin jar to "isolate" it from the car...not sure if this helps battery life though...

Any similar bad experience from someone?

Thanks for your support.
2017 94Ah

Pahaska
Posts: 77
Joined: Thu Jul 30, 2020 11:49 am

Re: Remote Key fob battery discharging problem w. Easy access

Fri Oct 09, 2020 8:45 am

I typically experienced years of battery use in all of the past cars I have owned that had similar fob access. I have had my I3 for 3 months now and no fob battery problems to date. One fob is new because the dealer had only one fob when I bought the car. The battery in the newer fob has been in use for an unknown period. I have always used the original fob and stored the newer fob in a kitchen cabinet.

eNate
Posts: 767
Joined: Mon Sep 09, 2019 5:33 pm

Re: Remote Key fob battery discharging problem w. Easy access

Fri Oct 09, 2020 9:10 am

How do you normally carry your fob during the day? I think it's likely a button is getting pressed inadvertently causing excessive drain.

These remotes operate in a low-energy "listening" mode and don't transmit unless they detect a signal from the car, which itself is relatively low-energy and shouldn't have enough range to be detected more than a short distance. Additionally, the car shouldn't transmit unless one of its touchpoints is activated.

I wonder if it's possible a stray frequency could fool the remote into coming alive? I suppose your Ferriday cage experiment would prove or disprove that.
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Neil
Posts: 61
Joined: Sat Sep 06, 2014 10:11 am
Location: Davis, CA USA

Re: Remote Key fob battery discharging problem w. Easy access

Fri Oct 09, 2020 1:56 pm

I recently replaced the battery in my key fob after getting the low battery warning message when I got in my car a few weeks ago. I've had my i3 Rex since 2014 and I think this is the 2nd or 3rd time I've replaced the battery. It is possible part of the system is defective, that is, the fob itself or in the car.

Do you have another fob you can use and see if the results are the same? I'm also assuming that the batteries you are using in the fob are fresh and of good quality.
Neil L.
2014 i3 Rex, Giga World, all the trimmings.

Bertone
Posts: 30
Joined: Wed Jan 22, 2020 9:37 am
Location: Madrid, Spain

Re: Remote Key fob battery discharging problem w. Easy access

Sat Oct 10, 2020 10:19 am

Well...don't think my key is being pressed while I'm in the car driving.
When I store the key in the jar, in fact it is a blue Nivea tin jar, the car cannot be opened if locked before. So I'm sure there is no communication between the car and the key while the key is in the tin jar.

Will swap to my second key to see if this battery lasts longer.

Thanks for your tips.
2017 94Ah

SwissDI3
Posts: 27
Joined: Sun Dec 17, 2017 2:34 am

Re: Remote Key fob battery discharging problem w. Easy access

Mon Oct 12, 2020 12:13 am

My 2017 I3 is also equipped with comfort access and the batteries in both my fobs are now 3 years old.
The car gets used frequently (approx. 52k Km now) and no sign that the batteries need to be replaced.
Same result with a similar I3 of a friend of mine.

The life you are getting out of your batteries is definitely not OK!

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