Hi Folks,

New to this forum and hoping someone may have some words of wisdom for me. I purchased a 2009 XK convertible this past summer and drove it sparingly, but enough to have run into a problem with it starting on several occasions. I would drive, park the car on an errand, come out a few minutes later and when pressing the starter button get absolutely nothing. Fiddling around with it and repeating the effort several times it always fired up eventually but with no apparent rhyme or reason. Since the fall I have had it stored in my heated garage with a trickle charger on it. Went out today to fire her up a bit and nothing! Battery is fully charged, dash lights came on, headlights and taillights, but absolutely nothing from the starter. The I could not even get the system to shut down - lights remained on and I could not get the accessories or lights to turn off. After an hour or so of frustration I did the trunk contortionist thing and disconnected the battery (I know - I'm going to have to reset some stuff when I reconnect it.)

Does anyone have a clue for me? Greatly appreciate it, thanks.

You can try depressing the brake pedal more firmly as that sometimes is what it takes if there isn't sufficient vacuum in the servo unit to assist.

Battery,Battery, Battery,

had and the same thing with the lights after I ran the battery low.
Put a multimeter on the battery and see if it’s below 12.6v

Thanks - tried that - stood on it to no avail.

Charge battery over nite see if that helps

Your symptoms are indeed the perfect symptoms of a battery either too low in charge (despite your statement that it is fully charged) or that fails the "load" test, meaning that it will not power the starter. The symptoms on these cars are often counter-intuitive -after all the lights went on - but they are the exact symptoms I experienced last year on a 2007 XK. A new and fully charged battery was the solution. Be aware that new batteries are almost never fully charged so make sure that any battery you purchase is charged *by you* before installation. Do not take the word of the battery store clerk!
By the way, the fact that you drove your XK "sparingly" since purchase virtually guarantees that the battery is the problem!

Thanks to all you guys for responding - I'd love to find it's the battery but I tried starting with a jump and still dead as the proverbial doornail...I fear Jaguar electrical demons.

Try pressing the START button before you step on the brake pedal.

I went through this last week, you are just going to have to find a sequence that your car agrees to. Read your manual, I have not had to do, but there is a way to start that basically bypasses the start switch, something about depressing the brake and slowly applying the gas pedal. Look it up to make sure you get it right but it may work.

Haven’t read that one anywhere before.

Hey thanks again for that - tried following the manual procedure and no dice!

Could be a lose or bad ground. I had this happen to me last year. Some how a nut on a ground post in the boot had managed its way off causing the starter to not engage.

If battery is fully charged and pressing and holding start button while at the same time foot on brake pedal HARD im stumped

If after all this excellent advice you are getting nowhere then you need to get stored diagnostic codes and problem solve from there. SDD has a routine to verify if you are getting ignition authorization and if not what is preventing e.g. brake pressure, start signal, security authorization.

Battery condition? You keep her on a trickle?