Thanks. Yes the car was locked and the keys were a quarter mile away. I did wash the car yesterday and had the trunk open and the car unlocked during that time, but that was only about 1.5 hours.

The longer "boot up times" for the touch screen seemed to be longer and longer each time I started the car, however. The battery is brand new! I think after a 1 hour drive or so, the battery should be fully charged, but using my seat warmers still seems to throw things off.

The car is a Select Edition warranty car, but I'd still like to avoid having to take it to the dealership if possible. If I take it to Advance Auto Parts and they test the battery, would I be able to get any useful information, or do I need a more specialized battery test?

 

As I've mentioned in previous posts, I have had this same problem and am on my third battery in a year. It is disconcerting to lock the car and still see the leaper logo staring at you.

My previous Interstate -93 batteries lasted about three months before the electrical problems resurfaced. Thanks to rscultho and CleverName's guidance, I spent the extra $$ for an AGM battery this time. So far,so good, but time will tell. This one has already lasted longer than the others before the gremlins woke up.

There has been some discussion re: AGM #s. As long as you are assured it's an AGM battery which for Interstate will run you about $250 - 300 USD, you should have better results. It appears from your previous post that you may have installed an h8 as opposed to an h8a, the "a" signifying the AGM.

 

Yup. So what do you think my first step should be? I do want the AGM battery but I don't want to go through the trouble unless it s fairly certain that is the problem. I have a feeling it is. BTW is the H8A exactly the same size (dimensions) as the H8?

 

Might be worth having the charging system checked. Could be an alternator issue.

 

HI,
Between my cars, motor home and boat I have been maintaining 10 wet cell batteries for decades. I got 13 years on my Trojan boat batts and 15yrs on M/H house batts!!
The secret is 3 stage CHARGERS and keeping fluid level above plates and if possible do a an equalizer charge once a year (16V!); all electronics MUST be disconnected for this.
Unfortunatly, I can only do this 16V on my boat (a $300 charger!)............

The AGM v's Wet Cell discussion is decades old; you get what you pay for! However, I've always got by very well using wet cells; being a cheapskate !
Unless you need to do aerobatics you normally don't need AGM's! unless you can't have a charger for the Wet Cells.
All my batteries are on chargers; the motor home on a $7 Harbor Freight 1 amp device.
My XK is on a Battery Tender Plus and the XK8 on a 10 amp auto and the Honda CRV keeps driven almost daily and no charger required.
This is the end of Batteries 101.........................

 

+1

You should definitely have your electrical system checked out.

When there is a battery tender on a battery you are effectively supplying electrical energy from your home's electrical system.

The difference between lead/acid batteries and Absorbent Glass Matt batteries is readily available to anyone on the 'net. There is a reason why high end automobile manufacturers are supplying AGM batteries in their cars.

 

Thanks to all the contributors on this thread!

I've been having some flakiness in the window movement on my XKR. I've not replaced the battery in the three years I've owned my 2001, but I'm quite sure it needs replacement.

I can confirm the previous information that the InterState MTP-49/H8A is the same battery as the new model id: MT5-49/H8. It is an AGM battery.

I'm getting mine installed at the local Kansas City InterState battery dealer for $293.

 

I just ordered a MT5-49/H8 from my local gas station--it should be here tomorrow!

 

replaced battery in 2007 xk. can't get top to go down now. that cover in trunk has to be just so. keep getting reading on my dash that says it is not in correctly. can anyone help or should i go to dealer. dash also said my hood not closed. i slammed that 3 times,so i know it it closed. I know somehow system needs to be reste as I did not have another source of power when I took out the battery.any help would be appreciated as my closest dealer is about 100 miles away. thanks

 

Do you have a local/nearby auto parts business such as Napa, Advance Auto Parts, Autozone, etc?

Usually they will reset the codes for you for free.

If after resetting them any of them come back you know you have an issue somewhere...

 

I had that issue and it was a hood sensor that need replacing. Try pushing the hood against sensor and if that makes a difference. My car had 25K at the time, so the sensor giving up early is not unheard of. Luckily the sensors are like $15 each.

 

You should first insure that the luggage pull cover is correctly inserted. There is a sensor. If it's not correct you cannot close or open the convertible. I had to fiddle with it to get it in right.

 

I believe BigOil is talking about the end that is closest to the passenger compartment. Try removing the entire luggage cover/top barrier and putting it back in again. I had the same issue when I replaced my battery.

 

One concern I have is the need to get a battery with external vent. The only replacements that I see offered locally will physically fit in the space and have the correct cold cranking amps, but do not have exterior vents. This could be a corrosion concern for an aluminum body vehicle. Does anyone have any thoughts on the matter?
Still have what I believe is the original battery in a 2004 XJR, or at least its a Jaguar OEM battery
thank
RyeJag

 

Yes, the vent is required.

Besides the corrosion concerns, if the voltage regulator were to fail, and the battery were to overcharge, excessive hydrogen gas can build up in a sealed interior. This is potentially explosive.

 

Can I know how much demineralized water we need inside the battery until which level, until 1/2 inch of the top? everytime I check a minimum of 1 liter is missing...its a 3 months new one but I am still skeptic and will double check.

 

After reading a lot of jargon, codes and abbreviated jiggery, I'm still none the wiser on what battery to get.

What's the verdict, dry cell or wet cell?
What does the car come standard with, wet or dry?

 

Fought with Jaguar for 3 yrs over defective battery. 48mo warranty expired, battery died. Bought frm Walmart: New batt with 900CCA, 5 yr warranty, installed and out the door in 30min!(Jaguar service good for at least 4 hrs!)
Total with tx=$129, peace of mind, thank you Mastercard!

 

Sadly, that battery will probably still fail prematurely. You need an AGM battery or you need to commit to use a battery tender all the time!

P.S. I replaced my battery in April (it's been about 8 months) with an AGM battery, and my screen hasn't frozen again yet. Seems to have been a somewhat permanent fix.

 

Pardon my ignorance what is an AGM battery?

RyeJag