I bought a 1995 Jaguar 3 weeks ago and I've been having trouble keeping the battery alive I use the trickle charger until its needed then I keep the car running to get the alternator working but after I turn it off and leave it for a few hours it goes back to no charge. I've made sure no lights are on to drain the battery when I leave the car. When I picked it up the day I bought the car it started up fine and I was able to drive it home.

 

Hello Fellow NewYawker. Downstate? Upstate? Western flank?

Sometimes one of the a diodes in the Altenator goes bad. When this happens the alt will still charge but if the alt stops and just happens to settle on the segment of the winding that have the bad diode the alternator will remain "excited" drain the battery. It kind'a like Alternator Roulette. This theory can be observed and tested. When the battery does die or gets weak be sure not to crank the engine. Hook up a battery charger, after awhile the Alternator will feel warmer then the rest of the metal surrounding it.

This of course is just one possibility and you may want to post in the X300 forum for more model specific possibilities.

 

Im near the albany area and thanks for this new info!

 

Another view:


1. the battery is badly sulphated from misuse and or merely age. It will not hold anything more than a surface charge that disipates quickly.


2. The car has a low grade short. that drains the battery. Hard to find,
Been there decades ago.


3. A lamp that should not be on is on. classic, the boot lamp.


Place to begin.


Place a VOM in series between the battery - post and it's ground on the wing wall. .05 milamp or so normal. Any thing greater is a problem.


Rougher: use a test lamo in lieu of the meter. Glow OK. Bright not good.


Finding the closed circuit or low grade short takes a lot more sleuthing,


Carl