I have a 2000 Jaguar XJ8 Vanden Plas - it has a new battery and I have had the alternator checked. However, if I let the car sit a week or so, since it is a Sunday driver, the battery is dead and needs to be jumped off. It is like something is pulling on the battery as it sits in the driveyway. Any thoughts on how to check this and see what is pulling a charge (if that is the case)

Thanks in advance for any help.

 

There are a lot of threads on drains with advice so maybe read a few.

 

On my 3rd X308 and each shared this issue lol.

 

Pay attention to posts 6 & 8 in this thread as you review it.... https://www.jaguarforums.com/forum/x...-drain-182813/

 

When you remove the key a switch makes from pin 4 to pin 5 which starts a security module countdown of agreements of other components of the car

Until the security module gets the agreements it will stay in a higher power drain mode

Once the agreements are met the security module goes into sleep mode which is a much lower power drain on the battery

One of the agreements is the driver exit position of the steering column

To overcome this you can switch the column control from automatic to off

There are different approaches to freeing up the ignition barrel in / out switch

Some clean first before spray lube ( graphite best ) as old lube can thicken and be stiff

 

Look to the glove box and the light in the boot as likely suspects.

 

TheX308 takes about 20 minutes to POWER DOWN and 'go to sleep'. (about 30ma nominal draw)

It takes a while to see the battery current drop step-by-step from several amps to 30ma.

I usually open the doors and the boot lid but close all the latches to simulate CLOSED.
Put an ammeter from the negative battery terminal to the negative cable and watch the amps/current drop incrementally.

Pulling fuses and network connectors/modules can 'wake-the-car' and you have to start all over again to see what circuit the constant drain is on. (USUALLY the SCP network)