Car battery is always empty
yes it will but you want to check with the security system active to see if thats a issue as well and it will not arm if everything is not latched
I just checked the battery after fully loaded with a battery charger. First it was 12,8 va when I just removed the battery charger.
after a night standing. its not over 12,66 va.
Its not the battery right? if not I am going to check the relay
after a night standing. its not over 12,66 va.
Its not the battery right? if not I am going to check the relay
As i posted earlier. I dont think you have a draw i think your battery was too low which can keep the car from going to sleep or wake the modules up running the car all the way down. Now that you have a fully charged battery that maintained a full charge over night just monitor voltages over the next few days. In the overall scheme of things draws while they do happen are actually pretty rare
Last edited by Brutal; Aug 29, 2018 at 10:02 AM.
Buy a CTEK battery maintainer and use it daily to keep your new AGM battery fully charged.
Your 2006 4.2L XK (X150) came from the factory with a conventional "flooded" (wet cell) battery. Your new Mercedes Benz branded Varta battery is a different technology - AGM (Absorbed Glass Mat), which has a different charging profile. What that means is that your alternator might not be properly charging the battery, particularly if you mainly take short trips. To remedy this, use a CTEK maintainer - it is compatible with both AGM and conventional batteries and will automatically select the right charging profile.
There are many threads on this Forum about how to install a CTEK battery maintainer.
Your 2006 4.2L XK (X150) came from the factory with a conventional "flooded" (wet cell) battery. Your new Mercedes Benz branded Varta battery is a different technology - AGM (Absorbed Glass Mat), which has a different charging profile. What that means is that your alternator might not be properly charging the battery, particularly if you mainly take short trips. To remedy this, use a CTEK maintainer - it is compatible with both AGM and conventional batteries and will automatically select the right charging profile.
There are many threads on this Forum about how to install a CTEK battery maintainer.
Buy a CTEK battery maintainer and use it daily to keep your new AGM battery fully charged.
Your 2006 4.2L XK (X150) came from the factory with a conventional "flooded" (wet cell) battery. Your new Mercedes Benz branded Varta battery is a different technology - AGM (Absorbed Glass Mat), which has a different charging profile. What that means is that your alternator might not be properly charging the battery, particularly if you mainly take short trips. To remedy this, use a CTEK maintainer - it is compatible with both AGM and conventional batteries and will automatically select the right charging profile.
There are many threads on this Forum about how to install a CTEK battery maintainer.
Your 2006 4.2L XK (X150) came from the factory with a conventional "flooded" (wet cell) battery. Your new Mercedes Benz branded Varta battery is a different technology - AGM (Absorbed Glass Mat), which has a different charging profile. What that means is that your alternator might not be properly charging the battery, particularly if you mainly take short trips. To remedy this, use a CTEK maintainer - it is compatible with both AGM and conventional batteries and will automatically select the right charging profile.
There are many threads on this Forum about how to install a CTEK battery maintainer.

Would suggest you simply fit the correct battery for your car
P.S. ... but I'm pretty sure that Varta will put the Jaguar logo on the same battery if it fits and meets Jaguar specs. Varta is a German company that is owned by Johnson Controls. They often provide the identical battery for sale by retailers under different brand names at varying prices.
https://en.m.wikipedia.org/wiki/VARTA
Last edited by Stuart S; Aug 29, 2018 at 02:35 PM. Reason: Added P.S.
nice try, but that's not what i said. Agm is the superior battery technology, but the x150 charging system was not designed for agm and doesn't provide the optimum charging profile. Nevertheless, many x150 owners have successfully made the switch to agm without any problems. All i'm saying is that if you're having problems with your agm battery, a ctek may cure them.
i triedand varta does make jaguar batteries
When at first you don't succeed ...
Varta also makes batteries for ... Costco!
P.S. I still owe you for your advice to use the compact spare from the XJ SuperSport.
Varta also makes batteries for ... Costco!
P.S. I still owe you for your advice to use the compact spare from the XJ SuperSport.
Have looked at the battery today and stay neatly at 12.64 volts.
so it was not on the battery.
I took the battery to the car and did the test for the relay there. the multimeter is put between the battery and turns out to be 0.00. So no loss on Relay.
that is good news. Dynamo good. relays well! So the battery runs out slowly and does not appear to be good. Good tip that there is a difference between Flooded and AGM batteries. The alternator therefore does not charge the battery properly so that the battery runs out more and more slowly, so it is solved right now
so it was not on the battery.
I took the battery to the car and did the test for the relay there. the multimeter is put between the battery and turns out to be 0.00. So no loss on Relay.
that is good news. Dynamo good. relays well! So the battery runs out slowly and does not appear to be good. Good tip that there is a difference between Flooded and AGM batteries. The alternator therefore does not charge the battery properly so that the battery runs out more and more slowly, so it is solved right now
When you say "multimeter" are you sure you have it set to "amp"? You are not looking for voltage with this test but current (amperage) draw. A zero reading would seem too low since it is expected to have a miniscule draw all of the time.
1. Do the lights actually turn on? If no, then you have incorrectly connected the meter or you did not set the meter to read DC amperes.
2. What current reading do you see on the meter with the interior lights on? Considering that the lights and some of the electronics (such as the center display) will turn on, you will see a current draw of several amps.
3. You need to be careful not to turn on too many devices as the meter has a limit to the amount of DC current that it will handle. An internal fuse will blow within the meter if you apply excessive current through it. For example, most digital multimeters can handle up to 10A current. This rating typically is indicated on the meter case.
It is true that the optimal charging strategy differs for flooded vs. AGM batteries. However I doubt that is the root of your car's problem.
Last edited by Patrick Wong; Aug 30, 2018 at 07:40 AM.
To the OP, when you shut the door click the lock button on the outside door handle twice. This tells the car to go to sleep immediately and will help keep the battery from draining.
It's very simple XK's require a fully charged battery! it doesn't matter what type (wet cell or AGM) .It seems you didn't have a fully charged battery (new usually are not!).
I personally use a wet cell and a CTEK charger always connected BUT many members use AGM's without any problems....as long as you use a charger to maintain
adequate Voltage .Even my Dealer now understands this!
Cheers, Adrian
I personally use a wet cell and a CTEK charger always connected BUT many members use AGM's without any problems....as long as you use a charger to maintain
adequate Voltage .Even my Dealer now understands this!
Cheers, Adrian










