2012 XKR v8 500bhp+ supercharged
23k miles
In garage as away all of September
Started first time on return
Used following week locally
Car used last 3 days local runs
Battery low— start engine - run for 30 minutes message on touch screen today
Battery 20 months old
Put on my CTEK charger 2 hours ago
Went straight to setting 3 and there for last 2 hours
Is this normal??
Have I connected leads correctly?( understand negative lead to chassis and not to negative battery terminal on an XKR) see photo

 

The right way to charge the batt is removing the cover on the left side
in the back of trunk. There is a pole with a rubber cover on it for the positive
charger lead to connect to.

 

Leave the charger on overnight, ideally in a location where you can see it with the car locked. See if it shows fully charged in the morning.

Richard

 

Pretty sure the 5.0 has a Battery Monitoring System and they don't want you connecting it right to your battery terminals. Terminals are fine on the 4.2 cars.

 

Ctek direct to Positive terminal is ok. Negative should connect to a chassis ground point.

 

To answer your question about the CTEK behaviour: yes, depending upon the condition of the battery it is entirely normal for the CTEK to remain at one of the charging stages for a considerable time. This will vary according to the charge level of the battery…why do you not make a permanent connection of the CTEK unit to the battery system? That way you can leave it connected and monitoring the battery whenever the car is not in use…and leaving it connected for months at a time is perfectly safe. The CTEK units are reliable, safe and very sophisticated charging devices.

 

Yes, will take hours, usually overnight,for the CTEK to reach maximum charge. It's intended as a maintainer, not a charger, which's why it takes so long and typically you'd leave it on charge at all times. As others said, positive to positive post and negative to chassis earth.

 

I use the remote battery terminals in the trunk (boot). The positive terminal is behind the black plastic cover on the left side:


Remove the cover and you'll find the positive terminal under a black rubber cover. Attached to that + terminal is the red alligator clip from the positive pigtail of my battery maintainer:


The negative pigtail of my battery maintainer is alligator-clipped to the remote negative battery terminal in the spare tire compartment. It's hard to find because it looks like a bolt protruding up from the floor. It's almost in the center, very close to the rear most part of the trunk (boot) by the bumper and may be under the spare tire, like mine:


I leave the pigtails attached to the remote battery terminals and plug them in to my battery maintainer after I'm parked in my garage. The trunk (boot) lid closes over the wire to my maintainer and latches without any problems.

 

Any bolt will do, as long as it's an earth. Both of my croc clips are fixed behind the black plastic cover.

 

Of course, you can use any "good" chassis ground, but how do you know that it's a good ground? My 2009 Owner's Handbook says to use the remote negative terminal in the trunk, so that's what I do.



For the 4.2L models, you can also use the eyelet connectors to permanently attach the positive and negative pigtails directly to their respective positive and negative battery posts.

The 5.0L models are similar, except for the negative battery maintainer pigtail. Because the Battery Monitoring System Module is attached to the negative battery terminal, the negative battery maintainer pigtail must be attached to a chassis ground. Otherwise, that BMS Module may be damaged. For a complete discussion of the BMS Module, see:
https://www.jaguarforums.com/forum/x...change-241034/
it's the same link as in the DIY Maintenance "Sticky" at the top of the first page of this Forum.

 

For an OEM style I did this in the boot. Easy to connect and get a visual on battery charge status.

 

Why is it not recommended to connect the battery maintainer leads directly to the battery?

 

For yours it’s acceptable, but for 2010+ 5.0 litres with BMS, the charging current must be before the BMS otherwise it will affect the BMS monitoring of the battery’s charge status.

 

I don't know but on my 2008 xk I charged the battery using the posts and then had an alternator failure. Read in a thread that there was in fact an issue doing just what I did with the 2007~2009 years...so? It killed two diodes in my oem alternator. If I had disconnected the battery and charged just the battery that would have been okay.
wj

 

Because doing so by-passes the battery monitoring system…it is complicated. But it is just as easy and as quick to make the connections properly: the negative to the stud on the trunk floor and the positive to the monitoring module. The electronics in these cars are complex and expensive…why tempt fate?

 

The 4.2 does NOT have BMS. Mine’s been connected directly
for 10 years nearly without any issues whatsoever.

 

See post #13

 

jahummer, Thank you. I was hoping that I had not mislead the chap that bought my car. I too kept mine on the maintainer directly connected 24/7 with no issues. The learning curve continues. Learned something.

 

 

Is anyone suggesting that it does have bms?
In my situation I killed the battery and simply put my trusty 40 amp charger on the battery, while still connected to the car's electrical system. Next thing I knew I had blown out the alternator.
Somewhere there is a Jag warning about doing that to 2007-2009., but it seems reasonable that a smaller charge would be less likely to cause damage.