Earlier got into my F-Type and pushed the 'Start' button(brake pedal depressed). Got message," Smart key not recognized. Hold it near the dash in the location indicated, and try again"
It was displaying the lower left dash near the trunk release button. I did this and on the second try, the car started. Later after a shutdown, I started the car normally with the key in my pocket.
This was a key I use as a backup, and had not used it for about 2 months. Doubt the key battery is low.
Anyone seen this before?

 

I think the battery will run down even if the fob isn't actively used - I've just replaced the batteries in both my fobs, one of which I rarely use, and the battery voltage was the same (2.65V) in each - they were previously replaced at the same time.

 

Fairly common thing in my 5 years of ownership. Been there done that on the battery changes but it happens about 2-3 times a year anyway. I would chalk it up to “quirky British electronics” but it happens with my 2019 Mercedes E450 at times as well. I’m convinced it’s partially related to the signal getting partially blocked by the pants I may be wearing or it’s just the electronics saying “f-off I’m sleeping right now, come back later”.

 

I've seen that on rare occasions. Most recently, when the battery was going low. They have a lifespan of around 4 years, it seems. I didn't get any 'battery is low' messages like the manual said I would. Suddenly, one day, it was dead and I had to use the manual key.

 

+1. I had the same experience with my keys.

 

I've had it as well. I've traced it to having something metallic (cell phone) in the same pocket.

 

Now that theory make sense to me. Competing RF signals. Or the metals acting like a faraday cage.

 

It does it to me all the time if my cell phone is in front of the key fob in my pocket.

 

If my keys and pager are in the same pocket happens every time.

 

Pager?

 

Thx All. I particularly like the "Lazy FOB, "F*** all, I'm going to sleep". Apropos for these times.
I changed the battery, and it seems to be working normally. This fob had not been used for about 3 months. I usually have keys in pocket without phone(or pager??). The second time I had a failure, a day latter, I again held the fob near the left side dash, and still got a failure message.
Now I have to decide to change the 2nd fob, or wait. Being cheap, I may just wait.

How do you start the car with a dead FOB using the manual key???

 

I found that in order for the fob to work when held against the magic spot in the dash, you have to turn the car off, open the driver's door to reset the starting procedure, hold the fob at the magic spot and then press the start button.

 

I didn't try to 'reset', just changed the battery. Today I will change battery in the unit I have been using daily. It is likely getting low, as they should both be about same age.

 

When my fob battery died just shy of 5 years, I checked the spare that had never been used. That battery was dead too. A number of us have seen the spare key battery die around the same time as that of the primary key. Always change both at the same time. They’re cheap. You can get 10 of them for less than $5 on eBay.

 

I just replaced both batteries, and also the ones in my wife's SUV ket. All about the same age.

 

Happened to a friend too (not on a Jaguar, either).

I ALWAYS replace FOB batteries for each car at the same time.

I only buy the two-pack, so as not to install OLD batteries on the next cycle.

 

Yes, the FOBs that unlock cars as you walk up to them are emitting signals. That is going to run down the battery whether you are using it or not which is why those who are not using both FOB's will have the second FOB need a battery replacement around the same time as their normal use FOB.

 

I avoid that problem by having my second/spare fob fully disassembled and ready to take a new battery if/when needed.
I suspect there would be nothing worse than being in hurry, finding your fob battery has gone flat, then grabbing your spare fob only to find it is also flat and you have no spare battery!

 

Or just keep extra batteries.

We have a battery storage bin with extras of every type of battery that is used in our household. When we run out of a certain type, we just order more spares. In the case of the FOB's, 4-5 years is usually the typical lifetime so you have some time to get those spares.

 

Sorry if I wasn't clear, of course I have spare batteries on hand!
My main point was don't leave a battery in your spare fob otherwise it will go flat even if not used.