I bought a 2016 XJL last month. Starting yesterday the rear passenger window has been going down by itself. I was able to t roll it up yesterday and it was still up very early this morning.
But I just went out to the garage and it went back down by itself! I wasn't even near the car.
Any thoughts??
I'm in the United States so driver side is in the left....passenger on the right

Thanks!

 

My low battery light just came on. I am guessing that is part of the problem?? Anyway, I just put a battery tender on the car

 

Did you attach the negative pigtail of your battery maintainer to the negative battery terminal? Or to a chassis ground?

 

I did not attach any thing to the battery itself. I am using this thing


I plugged one end into the electric socket on the wall and the round end into the little 12v thing in the center console (lifted the lid first). Maybe that doesn't charge the battery?

 

I just drove the car on the highway for 40 minutes to charge the battery back up. I've only made very short 3 mile commutes to the office since I bought the car six weeks ago due to COVID and very cold weather here in Wisconsin.. No highway use in those six weeks.

I am now using this thing on the car:

https://www.prestigeimports.net/tric...ry-maintainer/

Hopefully this will help keep from my window rolling down by itself



r

 

parnelli,

That Porsche battery maintainer won't work on your XJ because it plugs into the auxiliary power socket. That socket is on a switched circuit, which means that it is on when the ignition switch is on and off when the ignition switch is off. You may think that socket is always on because when you open the door that socket has power before you press the start button. That's because opening the door activates Convenience Mode, which turns on the interior lights and other circuits, including that socket. When you leave the car and shut the door Convenience Mode will automatically shut off after a few minutes, and there will be no electric power to that socket.Read this thread:
https://www.jaguarforums.com/forum/x...attery-225780/

And this one:
https://www.jaguarforums.com/forum/x...lation-130801/

Note that the XJ uses a Battery Monitoring System Module that is attached to the negative (-) battery terminal. Never attach the negative pigtail from your maintainer directly to the negative battery terminal; doing so can damage that Module. Attach that negative pigtail to a chassis ground.

Stuart

P.S. The stop-start system on your 2016 uses a capacitor instead of the small auxiliary battery on my 2013. The comments in the above links about the auxiliary battery do not apply to your car.

 

Stuart-

thanks much for that info. It is a bummer that that battery tender I had hooked up it doesn’t work when the car is off

admittedly I am not very mechanical so I don’t know much about hooking things to the actual battery. I guess I will just have to drive the car more often on the highway. I just hope that the battery is that beyond repair.
I looked through my files and I believe the battery is the original one that came with the car.
So it would be almost 5 years old and have 35,000 miles on it.
The dealership had the car from late October 2020 until middle of January 2021. I’m guessing it just sat at the lot (in the cold weather) and it didn’t get used much and that drained the battery. Then since
I bought it in the middle of January, it’s only been driven on very short trips in the city.
If I put a lot of highway miles on it in the next week or so will that help recharge it and keep it in good shape for a few months?

 

Ok, so the dealership says that there is a charging outlet that I can plug that battery tender into in the backseat on the lower portion of the center console.
I guess the question is, does that charging outlet also not work if the car is not turned on?

 

I am skeptical about what your dealer told you, but your 2016 may differ from my 2013. Regardless, you need to replace your battery ASAP, because cold weather is a battery's enemy and you're likely to get stuck again with a dead battery. I had Pep Boys replace my original battery with a Bosch AGM battery s couple of years ago and am very pleased with it.
https://www.jaguarforums.com/forum/x...attery-212478/

You should read your Owner's Handbook, particularly the section about Convenience Mode, and determine if that "charging outlet" will work to plug your Porsche maintainer into and charge your battery.

If that doesn't work, buy a CTEK battery maintainer that will.

More threads worth reading:
https://www.jaguarforum.com/threads/...issues.122844/

https://www.jaguarforums.com/forum/x...r-54755/page2/

 

Thank you so much Stuart!
I’ll just plan on getting the battery replaced. May I ask how much it cost you to get yours replaced with labor?
I’m getting price quotes of $500 from an independent mechanic and $600 from a Jag dealer installed.
Seems a bit high

 

Obviously, you didn't click on the first link in my previous reply (Post #9). If you had read it, you wouldn't have asked how much I paid for my new Bosch AGM battery. I paid $175.99 plus tax installed, including a 4-year warranty.

Why do you think I included those links? You may not be mechanically inclined, but you appear to be sufficiently computer literate to recognize a link and know what it's for.

Those dealer prices are rip-offs. Milwaukee is a big city with lots of places to buy a new battery. Click here to find a Pep Boys near you https://stores.pepboys.com/search.html and call other national chain auto parts stores to compare prices.The button at the bottom right corner is there for a reason. If you find posts that are helpful, press it - that's the Forum etiquette for saying "Thanks".

 

So sorry Stuart, i was reading your earlier post on my cell phone and did not see the 1st (of the three) links. At age 54 my eyes aren't what the used to be

You've been a great help. MUCH appreciated.

I had an indy look at the battery today. It was installed when the car was made in April of 2016. So the battery is nearly 5 years old and it is time for a new one. It will be installed tomorrow. $490 counting labor.

I am a bit disappointed because the car was a 'CPO' car when i bought it just six weeks ago. Was told that the car had everything replaced that needed to be replaced during the CPO process and that the car was good to go for a long time. That is why I bought a CPO car. Clearly the battery should have been replaced as part of the certification process but it is what it is I guess.

It's been driven 5-6 days per weeks since I bought it. Albeit on short trips.

Anyway, thanks for all of your help once again!

 

My advice to call Pep Boys and the other national chain auto parts stores near you apparently fell on deaf ears. Your car, your money, your choice.

 

I've got a question: I have been using the jumper connection (positive) under the hood and negative to engine ground to maintain my battery. Everyone else seems to be connecting in the trunk. Am I wrong?

 

Wow $490 for a battery and install!!
.
.
.

 

I replaced both the starting battery and the start/stop battery on my 2013 XJL for $375, and that included the replacement battery cables for the start/stop battery which uses traditional motorcycle terminals. Both were AGM, and higher AH ratings than the originals btw. The dealer quoted $1400.

 

Yes, you are wrong. The jumper connection under the hood is used to provide power to the trunk (boot) release because the XJ does not have a mechanical key slot to unlock the trunk when the battery is dead. Open the trunk and connect your charger or maintainer to the battery. Remember to connect the negative pigtail to a chassis ground and not directly to the battery.

See Posts ##2 and 3 in this thread:
https://www.jaguarforums.com/forum/x...minals-211754/

Here's how to connect your maintainer:
https://www.jaguarforums.com/forum/x...lation-130801/

 

I'm in Milwaukee also. I'll do it for $300 parts and labor next time. If I see another XJ out on the road, I'll keep an eye out for you.