Battery Going Flat

[Russ68]

Hi all,

I have an intermittent battery fault, she can be fine for months, then suddenly go completely flat overnight, without even enough power to unlock the doors. My only option has been to manually unlock the boot and jump start when this happens.

I don't think the battery is duff, she takes and holds a good charge, but is at least 2 years old, probably more. I'd change the battery if this was recommended. I haven't been able to isolate it and wondered if the X200 was known for this and if there are any recommendations as to how to resolve it. 

Many thanks, Russ

[Old Peter]

Hi Russ,

I would get the battery checked  --  It could well be on the way out.  Most garages/accessory shops have the battery tester handy.

My s type has been brilliant since I changed the battery a few days after Christmas  --  no more "Parkbrake fault" or anything like that.

Regards,

Peter.

[JOE-DOT-COM]

Hi

Get the battery load tested, but once they go completely flat, there never the same again

You need to find the fault first, for a battery to go flat that fast you have  some serious load, you need to connect the a ammeter to see what amps are been drawn and start pulling fuses til its gone, but it going flat that fast it could be alternator, its connected directly to the battery and when the rectifiers/diodes fail can cause that fault

have a look here for typical battery current drains and time delay BATTCARE.pdf

check any after markets addons, like stereo's, alarms etc

cheers

Joe

 

[Russ68]

Thanks guys, no addons like that and I suspect the alternator. I've had enough battery issues with other cars to know this is not a slight drain, interior light or similar. It's all or nothing, it'll either last for weeks / months, or go twice in consecutive days, and that's a big battery to drain in such a short period!

I also have a pretty awful squeak from the front belt area of the car and it which I wondered if it could be alternator bearings, so it would be great in a new alternator sorted both issues! I'll pop the mulitmeter on it in the 1st instance and have the battery tested, but I'll leave off fitting a new battery unless I have a better idea in what's causing the drain.

Where do we all stand on new vs remanufactured alternators, not done a full search but the new ones are pricy! Won't go with just a 2nd hand one as I don't want to do this job again anytime soon!

But once sorted I'll treat to a new battery and in the meantime I'll make sure the retaining thread is lubed up as I understand these can corrode .

Thanks, 

[JOE-DOT-COM]

Hi

Remanufactured alternators should be good, as it will be a Jaguar alternator, just stripped and rebuilt

usually bearing and brushes are changed and tested, better companies will offer longer guarantees

most jaguars use smart alternators, so they can alter the output, so better economy can be achieved

cheers

Joe