With my smart key in hand, opening the driver's door this morning, the horn alarm triggered, albeit very faintly. Neither smart key would deactivate the alarm or turn off the very dimmed headlights. After a few minutes the horn alarm turned off and a few more minutes the dimmed headlights also turned off. I tried the smart key to lock, unlock and open the trunk neither function worked. Prior to this no battery problems at all. I use a CTEK during winter storage. Sensing it was a weak or low battery I connected the CTEK trickle charger. It has been on for a couple of hours, the smart key functions, the horn and headlights also back to normal and the car starts fine. I should point out this is the original from new battery when I took delivery of the car. I am concerned that even thought the car is starting again, that I am out somewhere and it doesn't start. I am OCD on reliability, so I am sensing it is time and wise to have the battery replaced. Any members experienced this same problem and any the cost to have the battery changed. Appreciate any feedback.
Cat2

 

1st logical question is how old is the battery. Next would be how many times is the car used per week and then is it local or highway travel.

 

No need to be concerned about reliability...the Jaguar is telling you that you need a new battery (and that CTEK unit should be used regularly - it is primarily a battery *maintainer* not a charger.

 

Thank you for your kind replies........

sov211 & jagtoes, the original factory battery was replaced with a new battery when the car was originally purchased and plated in April 2010. So I think the CTEK has extended the life of this battery, but seems to me 6 years for a battery is pretty good. I use my car May to November then store it away with the CTEK on all winter. I use the car only 3 to 4 times per week, try to avoid short trips around town and try to stretch its legs more on the highway. This past week was more local driving in hot weather. I have a call into the Jag dealership to arrange for a new battery. Appreciate your advise.
Cat2

 

I just replaced the battery in my 2010. Well I did not do it, AAA did it in my driveway. Battery has more crankingpower (900+ amps) than the original. Total cost was $184.


The AAA guy also reset most of the items that need to be reset after the new battery. However he did not know about the passenger seat back not returning from the recline position, or the "service engine" light coming on because of the battery replacement. The local dealer took care of those problems.

 

The Service Engine reset takes about twenty seconds. There is a step-by-step around here somewhere.

 

Well the car did not start again yesterday after sitting for a couple of days. I was able to put the CTEK on for a few hours to get it started. Arranged with my local Jag dealership yesterday, they tested the battery and no surprise it was shot. They installed a new factory battery. Back on the road in less than an hour. All is good. I guess 6 years for a battery is better than average, no doubt the CTEK over the winters extended some extra battery life. The service advisor at Jaguar did recommend to always lock the car which automatically shuts down most of the on board systems using battery power. I never locked the car ever when it is parked inside my garage. Anyway problem solved, much obliged for the input on the forum.
Cat2

 

Totally agree with this post.

Be sure to use the CTEK when the Jaguar is sitting idle, even though you installed a new battery.

..

 

Dupe post ..ignore.