Yes, I know battery drain has been covered many times. My contribution is check the accuracy of the OBD connect. Brand of my bad OBD connect is Veepeak. I was ready to replace the alternator based on OBD/Fusion showing 13.8 (while driving) and dropping to 13.2 at idle. Decide to double check using a cigarette insert voltage display. It showed 14.2 dropping to 14.1 at idle. Connected DVOM directly to battery while running. Same 14.2 Removed OBD 1, installed spare. Now insert voltage and OBD/Fusion same number. Great no new alternator needed. Battery is 2 years old. Only charges to 12.5 w/ C-tek connect multiple days. New battery time.

Next problem is to figure out 320 mA drain when car is fully asleep. This is with AC off, stereo off, infotainment screen black and single button lock. It used to take 2 clicks to beep. Wonder how long a new AGM battery will hold enough juice to start the car. Car stored in a shed and I drive when weather is nice. Charger isn't an option.

Thanks for any feedback. Hope everyone has great weather to drive.

 

320mA is a massive drain and should not be too difficult to trace by pulling/testing fuses whilst the car is fully asleep. The car can be fooled into thinking that all doors/bonnet/boot etc are closed.
As a rough calculation, assume that the battery is 100 Ah and that you are prepared to allow it to run down to 50% charge before you start to see faults appearing. That's 50A delivered in an hour so 320 mA would take 156 hours or about a week.

Richard

 

Thanks for the expert advice.Much appreciated. Tested my 06 XK8. Drain quickly drops to 70 mA. Good enough? I'll check again tmrw morning.

 

The quiescent current drain of both the X100 and X150 models should be below 30mA so there is obviously something which is drawing more than it should or an accessory or aftermarket component might have been fitted. However, 70mA is not the end of the world whereas 320mA is very likely to cause problems in due course.

Richard

 

I had the same problem, and sorted it for about £20. I bought a 9W solar panel and charging controller off eBay, put it on the roof of the garage, and connected to the battery when I left the car inside.

Now I have a different problem because I have lost the use of the shed. I have found a similar, cheap solution. A small solar panel that sits most of the time on top of the dashboard and is permanently connected.

I did a brief write-up about this with photos a year or two ago. Maybe a Forum search by Google for solar panel will turn it up?

 

Wanted to follow up. Good news. Measure today is 4 mA. After 12 days, battery voltage down 12.8> 12.6 Problem? Needed to zero out the (pro quality) meter which was way off. Also found that the "clamp amp" measure varies slightly depending on exact placement relative to battery cable. When parking, shutting off stereo, info panel (down to black), double click door locks (maybe just need once) all help to reduce drain. 2 year old non AGM battery (previous owner). May replace w/ AGM and retest . Thanks again.

 

Sorry typo. That's 40 mA.

 

For anyone new to using a "clamp amp", placement of clamp at right angle to the battery cable, centered as close as possible and in the same place each time are the keys. I tried moving the clamp up and down the cable and at different angles. Got very different numbers. Not much wiggle room with a trunk mount XKR 'vert battery.

I'll check again tonight. Maybe 40mA based on earlier today.

 

It sounds as if you're getting to grips with the clamp meter but for very small currents I always use my digital multimeter on the lowest amp setting in series with the battery terminal. The readings are very accurate and you can watch the current draw reduce as the car progressively shuts down its system over the minutes following locking. It's a bit fiddly to set up and you need a second battery with jump cables so as not to overload the multimeter prior to engaging the central locking.

Richard

 

@CA Jag , 12.8 for a new agm is not uncommon.
As for sitting in a garage… mine does regularly sit for 3 months, not on a maintainer. No issues.
But as it is in the locked garage, I don’t lock the car thus the alarm is not activated and does not draw current.

 

Much to the chagrin of my wife, even unlocked my alarm will sound without a key nearby when a door is opened.

 

Always locking the XK when walking away helps reduce quiescent current draw.
See attached document.

 

Huh, must be a 5.0 thing, as my 2007 is always unlocked in the garage, and I occasionally open a door to grab something I need without having the key with me.

 

I think it is a passenger door thing.
wj

 

It does it to me also when I forget my key. Unlocked and alarm sounds when either door is opened. I said a wife thing because she beats me to her door by several feet and had to train herself to wait until I was closer before she opens it.

 

Unlocked...
I have mine set up that a single click unlocks only the drivers. Lot 's of my driving does not include my GF...so the passenger door remains "locked'. Assume I have parked the xk without 'locking', the next day I walk up with key in pocket and she goes to her side
If she tries to open the p door she is greeted with the alarm, if I had been a considerate BF and walked around to open the door for her (with key in pocket) the door is opened, she sits down and smiles... all is well.
ymmv
WJ

 

You may be right. Battery drain is almost a non-issue for the X-Type and the 2008 XJ.
Both XK/R FSJB and RSJB are different between 2007-09, 2010-11 and 2012-15.
Could still be a software issue, as it was the subject of a TSB early on.
Another reason to check for the latest updates.

Quiescent current investigation sounds like a fun project.

 

Success. Key is keep the clamp far enough from the battery. The clamp, near it, reads 220mA. I pulled the positive cable out and away from the battery. Clamp centered and at right angle. Got 20-30mA. Two year old lead acid battery seems to be holding a charge. Learning curve but the clamp is handy. I've removed the panel that covers the battery so easy access. If I don't see battery voltage drop over the next few weeks, will reinstall and stop worrying about it.

I shut the stereo off, climate off, infortainment screen to black and lock the doors. Seems to work.

Richard, agree meter wired in series is more accurate. Hopefully I won't have to trace circuits. Thanks for your help.
Guy, thanks for the feedback on AGM.
Bill400, thanks for the Quiescent Testing Guide.
CJ, found an 2011 XKR in Santa Rosa which is a 2.5 hour drive. It sold in 2 days. Looking forward to driving (buying?) one sometime. In the meantime, will enjoy my "slow" 07