Key Battery

elan2s

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So I have had the car 6 weeks and this weekend the remote on the key I use day to day stopped working. Having unlocked the car, using my phone, it would not allow me to start the car, even when I placed the key on the area in the armrest. Seen on other forums reports of short battery life with not just A6 keys but other models as well. Replaced the battery and all worked fine.

Two points have come out of this. Firstly I have now put a spare CR2032 battery in the car in case this should happen when I am a long way from anywhere and would strongly recommend others do the same. I had no prior warning of a low battery in the key before this. Second I think the short battery life issue on the most recent Audis is caused by the design of the key where the "Lock" part stands proud and is easy to get pushed accidently and for long periods of time. Washing the car recently I lost count of the number of times the car locked itself while I had the key in my trouser pocket.
 
I don't think the proud button and washing the car is related, it is the water splashing on to the door sensors that cause this if you've still got the fob on your person. It has happen with the majority of cars I've owned with keyless entry systems.

It is strange you never had a warning that the key battery was low as I have always had the warnings. Hopefully you were just unlucky and just had a dud one as I would expect up to two years of life out of them. The issue is the keys, unlike in the past, are constantly sharing information from the car...
 
I don't have the keyless entry system, just the standard push buttom remote so there are no door sensors. There are numerous reports on other forums of people with new Audi's having to replace batteries in their keys after a matter of weeks of ownership, maybe Audi has had a dud batch of batteries from Panasonic. Will need to see how long this battery lasts
 
I do think the new design of key makes it easier to inadvertently lock/unlock the vehicle.
 
There may well be a batch problem with the batteries, or like you say it could be the key in the pocket. It is very hard to work out which it is. The pocket problem is very dependent on the person though. With my A4, not once did the car lock, unlock or open boot accidentally, with my key in my pocket, and that was for over 2 1/2 years.
However since having the A6, in less than 3 months the boot has opened 3 times because of the key in my pocket. On one occasion it was late at night and I got a text from my neighbour saying "did you know your boot was open".
Clearly the key is different, but loads of people have had this with the previous shaped key, and I haven't experienced it, so I didn't expect it to start happening now.
Simple rule for me is, don't walk around with the key in the front pocket of my jeans!
The problem has certainly gone away now that I have a security pouch, I generally just pop the key in the pouch when I get home.
 
So I have had the car 6 weeks and this weekend the remote on the key I use day to day stopped working. Having unlocked the car, using my phone, it would not allow me to start the car, even when I placed the key on the area in the armrest. Seen on other forums reports of short battery life with not just A6 keys but other models as well. Replaced the battery and all worked fine.

Two points have come out of this. Firstly I have now put a spare CR2032 battery in the car in case this should happen when I am a long way from anywhere and would strongly recommend others do the same. I had no prior warning of a low battery in the key before this. Second I think the short battery life issue on the most recent Audis is caused by the design of the key where the "Lock" part stands proud and is easy to get pushed accidently and for long periods of time. Washing the car recently I lost count of the number of times the car locked itself while I had the key in my trouser pocket.
Ha. I had the same problem when washing mine. I figured it out straight away but it had me worried for a few seconds. Same with washing the rear - the boot opens.
 
The dealer told me earlier that the keys have movement sensors in them to prevent the repeater attack’s which have been documented for a while where the thieves hold a repeater outside your house and can unlock your car. If the key doesn’t detect any movement, the car won’t unlock apparently. Maybe that’s what’s causing the batteries to drain so fast
 
Quite the opposite, if the fob does have a movement sensor that puts it into sleep mode then it would use less battery power than one that is constantly 'talking' to the car.
However there has been no announcement that any Audi has this security feature and as far as I know only Ford and BMW has announced this for new models...