My car is still having to be jumped if left alone for more than 18 hours or so. We have installed a new battery and a new alternator. I have had the car tested (freebie at the neighborhood auto supply store) and the only thing they come up with is that something is draining the battery. I wanted to say "duh". Any thoughts? Hubby is trying to find out what it might be but is not having much luck. Thanks again everyone!!

 

The usual suspects are the radio and the interior lights. That includes the glove box light and the trunk light. Best time to check for interior lights staying on is in full darkness....

Best way to check the trunk light is for you to climb into the trunk and allow him to fully close it. Be absolutely sure he's willing to let you out afterwards, however....

 

Actually (assuming that the system is working properly) the lights will shut off after a period of time, to keep the battery from discharging.

I leave the trunk slightly open on my car to keep the wire from my battery maintainer connected to the battery. The light is on when I leave the car but off the next time I use it.

 

You can check the trunk light by closing the latch with the trunk open. Start with a screwdriver and use your finger to complete the process.

 

You must lock the car and arm the alarm otherwise it doesn't go to sleep.
This pdf will help if you want to measure quiescent current.

ps someone had the good idea of putting a mobile phone on video record into the glove box !

 

Regardless of whether the interior lights are supposed to turn off after a period of time, you still need to check them....

 

Steve, If I am reading that Document correctly, the X100 cars all have a 60 min. shutdown period, regardless of whether the security system is armed or not.

 

Paul,
Indeed that's what it says but there have been a number of members who complained of having their batteries go flat in a week or so - always cured by locking the car.
According to the pdf the XK series has two modes, quick shutdown when locked, longer delay when unlocked.
Maybe longer delay doesn't work ?
To avoid dispersing untruths I'll go and check mine now !!
Dead tractor so I'm not allowed to play with Jaguars today !
Found this which was what started the whole thing
https://www.jaguarforums.com/forum/x...y-drain-73957/

 

Could be. Prior to using the Battery Maintainer, I had varying Battery Discharge times.

Sometimes, I locked the car, sometimes not.

The time for discharge varied considerably. But I never considered the Lock Status as being a factor.

 

Check the littlle 'door' in the ignition key keyhole. If that gets gummed up and does not shut it can prevent the car from going to sleep.

 

I have been tracking voltage drop both locked and unlocked and do not see a significant difference, but it's higher than I would like. If I had to leave it somewhere for more than two days I would disconnect the battery. My XJ6 has no problem, as would be expected from a dinosaur.