I have been having electrical draining issues on my 2002 Jaguar  S-type automatic petrol car. Is it a common issue? what does Jaguar say?  My garage has been trying to find the fault but they come up empty-handed, the new battery that I have installed drains within 24 hrs. The battery is not at fault, there seems to be an electrical fault within the Jaguar that no one seems to be able to figure out. Are there any common faults that others have faced and what parts do you think I can change or try replacing that would fix my faults?

Find the alarm chirp sounder, under the wheel arch liner and behind the driver’s side headlight, and disconnect it. These Saunders have rechargeable batteries that degrade over time and short out causing a massive drain on the main battery.

hi

you need to find a better garage, finding a battery drain should be quite easy

you need to connect a ameter to the battery and check what the drain is after 40 minutes when the car goes asleep

would be a heavy drain if its going flat within 24 hours, really fast drain could be a faulty alternator

with the ammeter connected, you need to pull fuses and relays till the drain stops

any auto electrician should be able sort this

have a look here http://www.jagrepair.com/images/TSB/TSB2/S-Type/414Charging/S414-01am Quiescent Drain Current.pdf

http://www.jagrepair.com/images/TSB/TSB2/S-Type/414Charging/S414-02 High Quiescent Drain.pdf

cheers

Joe