How long have you had your AGM battery?
 

I just replaced 09 xk battery with AGM because of multiple discussions in the forum about advantages of AGM batteries. There is some question whether AGM should be placed in the xk 07-13 models because they accept charge differently and could possibly get overcharged and explode!! It seems many of you have placed agm's in your xk's, Jaguar recommends them in the older xk8's but not newer xk's. Wonder if this has to do with alternator recharge voltage. Has anybody out there had a problem with AGM after having it for a while? :icon_captain:

I've owned the car for two years. In the first year I replaced the battery three times because of the electrical gremlins - primarily the touchscreen issues.

The third battery, the AGM, was installed a year ago and I've not had any electrical problems since. I do not use a battery tender and more often than not I leave the car unlocked with the fob inside in the garage. The car has not exploded yet.

Interstate warrantied the batteries and I just had to pay the $$ difference between the lead acids and the AGM. I feel the price difference was well worth it.

Best regards,

I have had my AGM battery for almost a year. I was having touchscreen issues and transmission gremlins. However, they went away after I switched to the AGM battery--for a while.

Some of the problems come back if I haven't driven the car for a while (a week or more if in cold weather). The car is not a daily driver, and I don't use a battery tender.

About a year, maybe a tad less...
Flawless to date.....

Do you know how much energy you would have to apply to get a battery with that much capacity to explode???

An AGM battery accepts deeper and longer charges, as well as more frequent charging. Your car does not the ability to over charge an 880 amp battery (with all of the other circuitry in the car) to the point of explosion. More over, the charging system is intelligent enough charge your battery to a potential and then stop charging until the potential falls below a particular threshold. The stop charging is a little more involved if it were explained accurately but the concept applies.

I had an AGM battery in the 07 XKR I had for over a year and have had an AGM in my 2010 for the 2 years I've had it. I have never experienced any of the electrical gremlins others have (thankfully).

There is a reason why many of the high end car manufacturers put AGM batteries in theri cars.

I have never heard the thing about 07 - 13 XKR's and AGM batteries. That is hard for me to believe...not calling you a fibber, I would just have to see some hard technical evidence before I would believe that.

I've yet to see a person with these supposed battery problems ever detail what the current draw was/is on their cars with the key in the locked position or even with the key just to off after thirty minutes.

The 2007 manual says it should be less than 35ma if no other non factory items are installed on the car.

Have my AGM battery in now for approx. 10mths. My xkr has always been my daily driver. The electrical issues I experienced previously have not returned. The only change was the battery. So that was obviously the culprit. The most unusual electrical problem I had was for the touchscreen and radio turn off soon after I drove away. It all turned back on in an instant but then my hazard lights were flashing. Really weird the elec issues that can arise from the battery saga. As I said no problems since.

anyone worrying about an AGM battery exploding should worry more about a conventional battery exploding ........... because AGM's require a higher charging voltage.

i suspect that the battery charge problems in the later model years of all models relates to the ECM charging control. many manufacturers have dabbled with turning off or reducing battery charging according to software algorithms with the goal of decreasing fuel consumption.

i would just rather have a fully charged battery thanks.

Battery issues, charging issues
 

U can put a Fluke meter on that has a 24 hour recording that will trace whether ther is a electric draw issue or whether the battery cant keep it up. The Fluke meter can also give u a paper read out. I am not criticizing the xkr, but my experience has shown that new batteries arent the issue. Hi line cars often have problems. The more sophisticated the car, the greater the chance of an electrical issue. A 2013 xkr rag top has, under definition, at least 32 computers. Please do the math. I think the xkr is a great car, you just have to know what keeps it happy!

The issue isn't "the battery exploding" - it's the warning that AGM batteries suffer if you charge them at too high a voltage. From the workshop manual:

The implication is that conventional batteries don't have this limitation, and thus the voltage regulation is less critical. We know Jaguar recommends replacing like with like. The concern would be that, in a car with a voltage regulation system designed for conventional batteries, there is a chance that it might apply too high a voltage to an AGM unit. However, it seems that no-one has experienced any problems along those lines. The only thing we don't know is whether damage is 'silently' occurring that will shorten battery life - so far, based on what I've read here, we know they last 2 years without issue.

It's probably no problem at all, but that's the question that's been raised.

Thanks guys for all the useful posts! I am sure I made the right decision to upgrade to the AGM, it is just a better battery for cars with high electrical demands. I don't know enough about car electronics to be a "fibber" about it, just relating what I heard from someone with more knowledge than me. That's why I come to the forum to figure this stuff out from people with experiance with these great cars!

I knew that was the case.

Not only will an AGM battery work better, it will last longer.

Enjoy your Jag- you may have a collector's item in a couple years!

Great post fellows, very timely; conclusion? think I'll put an AGM in my wife's XK8 first !

Adrian

For the record the 09 xk convert. is my wife's, I drive the 10 xk coupe. I never told her about the exploding battery theory, didn't think she would be interested!

A question on Jag batteries.

BMW has different charge profiles for AGM and non-AGM batteries, as well as either technology as the battery ages.

Voltage applied from the alternator is adjusted to allow for both issues. New batteries must be registered (type, date installed, amp-hours) in the power management controller to set up the system.

Does Jag do something similar in its recent cars, or is it "install and go"?

Interesting...is that true for all BMW cars?

Don't know of any setup that is required in software for Jaguar cars - I've never experienced anything like that.

I'm grateful my Jag does not require this.

It's on all recent cars (last 10 years at least). The manufacturer data on its effect on battery service length is not available, of course, but the logic of lowering charging system demand, and thus manufacturing costs, makes sense. Perhaps because of German/Euro demands, the engineers spend a lot of time improving CAFE efficiency. I assume this is one of their approaches.

To pursue a question relevant to Jag, is it your practice to replace with a Jag battery, or (like most knowledgeable BMW owners) do you replace with an aftermarket equivalent with no ill effects? Which one, if so?

This is the full battery installation procedure from the manual:

I don't know what the reset procedure is - perhaps you do enter the battery type and capacity.

Interestingly, they have this warning:

There is no corresponding warning about fitting AGM batteries to cars fitted with a flooded battery as standard.

In my 2007 XK manual there is no mention of the BMS at all. I suspect that BMS is a for newer cars than my 2007 and I have a suspicion that the BMS is only for recording when the last battery was installed and not for any other reason. I'm just guessing and nothing more than guessing.

Hmm - looks that you're right - BMS only appears in the 5.0 manual.

However, it does more than that.

Thanks for the clairification. I looked in my 2007 manual and it wasn't there and I couldn't convince myself to download a 2010 manual to find out what the BMS was.

Seems it's sorta like on an airplane. If the main gen goes out then the stby gen comes online and those things that were on the main buss are now not fed anymore. Makes one wonder just what items and the order they are shut down when the BMS decides there's too much load on the system. Just musing .Not looking for an answer.

It's the ECM that does the shutting down. My guess (and only a guess): non-essentials like screen heaters, seat heating/cooling, maybe moving on to the climate control if things get worse - anything that is not essential to keeping the car running. In reality, with a 120 amp alternator, it's really only at cranking time that the battery is critical, so maybe that's the time when the ECM temporarily shuts things off. I guess it may also be the source of the "low battery, start engine" warning that you get if you sit with the car in 'convenience' mode for too long - I imagine a few things start to get shut down once that appears.

I installed an Odyssey AGM in mine a few months ago after getting tired of the nav screen locking up along with various other strange electrical anomalies. So far so good. Not a single issue since.

another perception
 

Excluding the antiquated nav screen there are other issues that should be addressed. The '13 xkr ragtop has a myriad of exposed wires that are begging to be dead shorted. Under the radiator shield there are multiple pin connectors with exposed wires going to them, among each shock there are 2 wires that are exposed that have no plastic snake covering, open wires to pin connectors for the ABS, if you take all the panels out of the trunk there are wires on both sides running along the body that are literally wire looms that have no covering. I went with my dad to buy this car for him. It took me 2 hours to go thru the electrical systems, including meters to ensure there wernt any dead shorts or frayed wires. When I pulled the center of the back seat out to have a look at the fuse box and removed the trunk pannels the dealer almost died when he saw the exposed wires and realized this was factory. (Wasnt a jag dealer) I went with cut heat dried shrink wrap wherever I can get to. I have been covering wires now for a couple of months and I should be done by June. I am not criticizing the car, but some of these gremlins and future problems are peventable if the factory would make more of an effort to provide better protective upgrades for the electrical system

Socal is this 13 xkr ragtop your car or your dad's and is it the same car that you replaced the pulley on?

I like your previous screen name better.

Whose car?
 

It is my car. I bought it from my dad. It is the "13 xkr ragtop. Same car that I changed the pulley on. I bought it from him for $65,000. less than 2000 miles on it. ( I had to change the screen name. Too much complaining fron the "good ole boys club"

Which model did you choose, and did it fit OK? I looked at the Odyssey site for their recommendation, and they said the PC1350, but noted "Vehicle battery restraint(s) may require modification." Did you have to make any mods to get yours to fit?

Wow, that's thorough! I should probably take a look at mine, considering we get a lot more rain here than you do. Had to drive through 6 inches of flood when I was in Wales at New Year. I'm less concerned about stuff inside the car, but anything that could be exposed to water should be protected (which includes anything under the bonnet, since fans are very good at flinging water everywhere).

It's not surprising that manufacturers don't go to that level of protection, though - the time taken to shrink-wrap every connector would reduce the rate at which looms could be produced. Or you'd need more staff, which increases cost. Not saying it's the right approach, but that's the reality.

Kudos to you SoCal for doing what Jaguar should have done in the manufacturing process. Jaguar needs to overcome their infamous reputation by going beyond industry best practice. Can you give us a simple post of how you've gone about this and what materials and tools you used?


Your dad gave you a great deal on his car. Why did he sell it to you and what did he replace it with? I bought my 2013 XKR in West Palm Beach, Florida, from a Bentley dealer. It had only 300 miles on it. the first owner never got in the car. He has so much money he buys 2-3 cars a month. He traded the XKR in on a new Bentley and when I bought his traded XKR his Bentley he bought on the trade was also on the lot for sale. Post some pictures of your car and the wires you protected. I'm impressed by how your protecting and making your car better.

Ami, Ami, Miami!!
 

I enjoy reading your posts. U r probably the smartest person on this forum. U bought your car in south Florida, like my dad did. There seems to be so much money in South Beach and the cars are in pristine condition. Cars in Coronado and Southern cal are of a different breed. Ferrari, Lambos, Bugattis are rpevalent but often get "bonsaied" along the PCH or raced on I-5. To see it seems that xkr's whether rags or coupes are throw away cars in South Beach. And by that I mean, people buy them and get rid of them in a month or 2, but they dont drive them or tear them up. I am going to post pics of the heat shrink wrap that I used and how I applied it down to the connectors and used a heat gun to shrink it more so than with a hair drier. Also I am going to post a pic with a factory defect on the application of the aluminum x- brackets above the radiator shield that arent visible without taking off the shield. The x-brcket is so flimsy that it drops down and catches the lip of the shield making its removal almost impossible unless a lot of critical thought is put into the removal and sequential pics made to determine the reason for th dropping down of the x-bracket. Once again I am not criticizing the brand, just pointing out thing s that need to be included on a world class car. For me a good analogy is that I would never go out wearing Versace with something like Michael Kors heels

I installed an Odyssey PC1700T in mine. It is a little bit smaller than the stock battery - both in length and width - but not by much. I put a piece of 1" wide .250" thick 12" long aluminum bar stock in between the clamp and the battery and that was enough to hold it in place.

I live a few minutes away from the dealers you are speaking of and ended up buying from a Pa dealer to get the best price on a super low mileage car (4,800 miles on 2010 XK). I found the dealers here asking premium prices for their cars just because they could. There is a captive audience here with deep pockets. SoCalBabe.........I too would be greatly appreciative of any pics you might be able to share showing the shrink wrap application. Here in South Florida we get torrential downpours which is a primary concern of mine with the undercarriage exposed connectors and wires. Thanks so much.

Any idea what the battery voltage is supposed to read? I hadn't driven the car in several days, and the voltage (according to the ECU) was 11.5V with the engine off. When the engine was running, it was at 14.0-14.5V, depending on whether I was idling or not. Then after a 20 minute drive, with the engine off, it settled back to approximately 12.0V.

A completely disconnected battery (i.e. with no drain from the car) should be over 12.5V if it's reasonably charged. The generator provides a 14V feed to charge the battery.

What if it's not completely disconnected? :D

Depends how much the car is sucking from it - which, if you've opened the door & are sitting in it, is about 10A. The load from the car reduces the voltage.

You can't really tell the true condition of the battery by slapping a meter across the terminals unless it's really low. It needs to be tested under load. Autozone has a nice setup they bring out to your car and they can test your battery and charging system for free.