Key Fob battery...

[emejay]

My 3 week old CT is showing signs that the fob battery is weakening, as sometimes the car will not detect its presence unless I hold the fob to the Power button. How long do these batteries last? Have others experienced the same occurence, but the battieries were fine and it is just a quirk with the system?

[Chunky1234]

Does it happen all the time or in one particular place? Reason I ask is this might be interference and not battery.

[abqpete]

When I was at the dealership test driving the CT, the sales guy was having exactly the same problem. It turns out that my Prius key fob was interfering with the Lexus one. When I moved the Prius fob far away, all was fine with the Lexus.

[emejay]

It happens both when I'm inside the car, and when I'm outside and try to lock-unlock the door by touching the handle. I don't have the second fob readily available, but I will get that one and see if problem is resolved, and if it is, I place fault on the individual fob/battery.

I had a remote control for a GM vehicle in pocket, I will stash that too.

Thanks for the comments.

[audi4t]

IPhone interferes with fob and my wife has a pocket book that shields the fob signal.

[Dirvin]

Ive never had to replace the battery in a Lexus key yet. I keep my cars 3-4 years so the battery lasts at least that long in an electronic key. I would assume the key fob battery is similar.

[nahtanoj]

I have the same issue...how do you know the iphone interferes with it?

[lostchild]

My wife has her iPhone in the same purse as the key fob and it works just fine. I have my iPhone in the left front pocket and key fob in the right front pocket and it works fine.

I would try the other key fob and see if it is the key fob or the car.

[audi4t]

If I have the iPhone and fob in the same pocket the car doesn't recognize the signal and the door will not lock/unlock. This must be a proximity effect. I guess this is why devices have the FCC warning signs on them. Devices can cause mutual interference.

My wife's pocket book that causes issues has a "metallic" finish - which I assume shields the fob signal. She can be standing next to the car and the door will not unlock until she takes the fob out of the pocket book.

[jessright]

The manual does say to keep the FOB away from other radio wave emitting devices as much as possible, or I guess as is practical to prevent premature discharge of the FOBs battery.