My car battery died now the fuel gauge is reading improperly. How can I reset this? I tried researching but couldn't find any answers to my issue. Thanks

- 08' XKR

Battery died.....fuel gauge shows empty

Not a perfect answer but may be useful. This link isn't about Jags and I haven't had the experience but it seems to indicate it may just take some cycles of running and it is likely to go back to normal. Jac

Fill the tank plum full, then remove the positive battery lead from the battery post and touch it to the negative post for five seconds and then reattach to positive post. This will reset everything.

Also, what does the RANGE computer indicate? Does it coincide with the improper gauge or with the actual fuel in the tank? Just me wondering...

My fuel gauge use to show 190mi on full tank. Now on full tank it shows 300mi which is way off

Probably lost its history of your driving habit, and needs to rebuild that.
When I first got my '07 XK, the estimate showed a 420 mile range for a full tank. Took a 400 mile drive, mostly highway, with no refill (but I was pretty nervous about making that last 50 home).
Since then, due to lots of local driving, the range estimate is much lower.

Battery was replaced in my car right before i picked it up. Still shows over 300 after a week of driving (but is descending...thank you sport-mode!).

Mine also is above 300 mile range on a full tank.

16.1 US gallons on a fill-up and 190 until empty.... That's some HORRIBLE fuel mileage you get.

On my 13 XKR with 3500 miles it shows a range of about 300miles on a full tank. Currently I'm averaging about 16.5 with a mix of about 50/50 city and freeway driving. Total freeway is about 18-20 I expect both will go up after about 10k miles on the odometer

Thanks for the reply guys! Appreciate it. Lol yeah your right. So 300mi until empty is actually reading normal then correct?

Given a 16 gallon tank and about 17-20 mpg, 300 range is where it should be filled up.

The fuel gauge in my '07 XK over-reads. The display seems to move in proportion as fuel is used up, but when it reaches half-full on the way down the tank is just about empty.

Would Cee Jay's procedure reset it? And why is it necessary to touch the positive lead to the negative terminal (post) rather than just waiting five seconds before reconnecting it?

TN

Touching the two leads together instantly drains all the volatile memory. Simply leaving it disconnected for a bit wouldn't discharge anything, and all the volatile memory would stay intact. Now, leaving it disconnected for a few DAYS would probably allow the systems to slowly discharge would probably work also, but why wait?

Thank you Cee Jay.

Could you tell me what else the procedure will reset on the car; anything I might prefer NOT to reset?

TN

The windows will need a reset, but those are easy. The top SHOULD still be OK, but run a full cycle anyway to make sure. The stereo should still be OK, the seats should still be set, all the vehicle setting will still be OK....... everything that has a Memory Hold function should still be set.
So to answer your question.... other than the windows (and maybe top), everything you would want to stay will stay as it is. I guess some people lose settings, but I've never lost any (sans windows).

Thank you. I hope you're right... but obviously, there is a reset procedure for the soft top if needed (he said hopefully...)

TN

Check your owner's manual. If you don't have one you can download one at no cost see the third or fourth entry on the home page of this forum.

Thanks for reply guys. I did a load test on battery and its not good. I did alot of research but i see so much different suggestions on what Group 49 to get. Do you guys have a model number for battery to get? Is AGM good?

Whatever floats your boat... I installed a Deka AGM on mine and it seems fine after a month of running. No more overnight charging. It was @ $225 with tax though.

I filled the tank right up, then disconnected the battery and touched the two leads together momentarily to clear the volatile memory. I didn't lose any settings bar the windows, but it hasn't made any difference to the fuel gauge.

So, we know it's not that (thanks CeeJay). Does anybody know any other simple fix I might try, or should I just go to the dealer, drop my trousers and bend over...