My '04 XJR has been sitting for 2 weeks and I went to start it today and just got clicking from the starter. I don't know how old the battery is buts its not the original (it has an exide now) and looks fairly new. As far as I know it was fully charged when parked. I'll clean the posts and get a battery tender but I'm a bit surprised it didn't last longer while parked. Is this normal for these cars? I've got other cars with with similar power drawing equipment and they have sat for a month or more and started. I guess if this is not normal I may need a new battery. Thx

Stu

 

Checked the battery further and its an Exide performance size 49 with 1000cca. I don't see this battery listed on the Exide website so maybe its older than I think.

Stu

 

Every battery manufacturer stamps a date code on automotive batteries.

If you are extra curious you could find the code and look up the date code system that Exide uses.

 

The car should make it two weeks and start normally if all is well. I would guess that 6-8 weeks might be pushing it though.

 

Did you lock it?
If so it shouldn't have run down.
First get the battery properly tested at a battery shop.
If it's OK come back + we'll start finding the leak.

 

If the battery is not sealed and you can test each cell, go to an auto parts store and get a hygrometer. That will show the condition of each cell, you may have one or more weak ones.
Good luck...

 

What is the history of the battery? Was it totally discharged at any time? Maybe couple times? As far as i know run down battery can loose up to 70% of the original capacity.
I had original Motorcraft battery in my Ford Thunderbird for over 14 years but never was run down. Replaced 2 years ago by A C Delco, the largest i could find, very happy with this brand.

 

You do not give enough information for anybody to help you. As Steverin france has already asked, did you lock the car. If not two weeks sounds about right because everything including the air compressor is still active.

Locking the car shuts everything down and puts the car to sleep preserving the battery charge until you wake it back up by unlocking the doors.

 

Thanks for the replies, no it was not locked Steveinfrance, and thanks Bob for the info, I did not know the car went into hibernation when locked, I don't recall reading that in the manual ( I wonder what else I missed, better have another read). Cleaned the terminals and have it on a slow charge, will test it when charged and lock the car from now on.

Stu

 

According to my Technical Notes of 2003, the air suspension 'Sleep' mode occurs 30 minutes after ignition is switched off and last door/boot lid activity has been detected. Locking of the car is not necessary to enter Sleep mode. However, the system 'wakes up' every 24 hours to check vehicle ride height and adjusts car to be level (if necessary), to the lowest corner. At no time is the air compressor switched on to replenish the reservoir, nor is any raising of the car done.

I have to say, I suspect your battery.