I have 2.97 amp draw on my battery when the car is asleep. I have checked all the mini and cartridge fuses and have found that cartridge fuse #25 in the luggage compartment is the culprit. This is a 40 amp fuse and it is labeled "Primary Junction box".

Other than bringing it in to my mechanic is there anything else I can do? What does this fuse control power to?

The only thing not working on the car are that the horn doesn't honk (audible car locked signal) when hitting the lock key on the key fob the second time. The lock/security works fine, just no audible signal - although it did honk just one time last week and hasn't since, so maybe a loose wire there.

Is the receiver for the key fob controlled by this primary junction box? Is that where I could have a bad ground or short? Or is this a coincidence?

 

2.97 A is a lot! I am surprised there are not other symptoms besides the battery going dead. I have never seen one that big.

I think I would take it to Jaguar but how much can you do yourself?

Open the primary junction box up and do the same thing. Disconnect circuits until you find it.
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Greetings ... I am very interested in your interpretation of "asleep" because I rather suspect you may not have yet consulted the Electrical section of JTIS workshop manuals, nor the actual wiring diagrams ... all available for download here, although I recommend getting them all with TSBs, updates etc in a disk based PDF format.

Firstly, JTIS describes the process whereby, normal operation provides a delay of at least 60 minutes until the car "sleeps" and in this condition draws an absolute max of 200mA quiescent current (if my memory is correct). Yours is 1500% of that. Even more important to your reported problems, it lays down which faults will prevent the car ever reaching this "sleep" condition.

Secondly, the correct wiring diagrams for your model and year will remove any guesswork as to what Primary Junction Box fuse #25 actually feeds. Suggest you read and test each circuit, step by step.

Best wishes for a speedy fix,
Ken

 

Thanks,

I have the wiring diagram and the technical guide. What is the JTIS and where can i get it?

I am a semi novice, so I can't seem to find the location of the primary junction box to try to isolate what is causing the drain. Can you tell me where it is and what it looks like?

 

Here's info on downloading the Jaguar shop manual, known as JTIS...
https://www.jaguarforums.com/forum/s...archive-66031/

 

Problem solved! Many thanks to all who provided suggestions.

Turns out the parasitic draw was only 1A, not 3A. When putting the multimeter between the battery negative cable and terminal I was "waking up" parts of the car, including the radio. When I removed the radio 20A fuse the draw declined by 1A.

Leaving this fuse out the battery now is holding at 12.5V.

All I need to do is have the wiring to the radio checked out and repaired.

I still have the intermittent "audible signal" when hitting the key fob lock twice, but I can live with this if it is also not just an easy wiring check as everything else (including the door locks and security system) works without the horn beep.

 

Great news Russ;

My long and detailed PM reply not now required, but good to know that we both deduced the same thing ... the very manner in which you were measuring the "sleep" current drain was "waking up" the car's electronics.

The most common trap, is not being aware that it takes at least an hour for the locked vehicle to achieve "sleep". A far more embarrassing trap is to leave the boot/trunk open to measure the current at the battery, and because it is sensed by the security system, this alone prevents the car from ever achieving "sleep". There's more ... but it's great to see you can put this one to bed.

Regards,
Ken

 

No. Even if the door or trunk is left open it will time out and shut the lights off. That is one of the main reasons the car has this feature. The idea is to always save the battery for starting. The 30 minute delay is in case you are working around or on the car.

Now any time you open or close the doors or change any other electrical draw the 30 minutes starts counting down again from that time.

You can prove this to yourself. Just switch the overhead lights on and close the car. Or just leave the trunk open. Check back in an hour and everything should be shut off.
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Yes; police666; I am not nitpicking here because what you describe of the lights dimming is absolutley true ... but that alone does not define the <200mA quiescent current drain when the car finally achieves its full sleep condition ... at least that's the direct word from the Electrical section of JTIS for my MY & VIN ... and it does state 60 minutes ... and that is what we have confirmed in the workshop.

Equally, your final point is true. When we check back in an hour, all the lights are indeed off. But again, "lights all off" is not of itself proof that the car has descended into its <200mA sleep status ... just that the lights are off. No more than that. The only way to test and confirm the final shutdown of all the control modules ... 17 at last count on my car, and that's not including the internal TCM ... is to arrange a remote current sense of total battery drain ... but we have to do it very carefully, because as Russ (moranlr) found, the very act of measuring the current drain can either inhibit "sleep" or "wake" some of the car's system components.

The most frustrating case I have wrestled with was a friend's X-Type with unusually high battery drain, which we finally nailed as a shorted sensor in the PATS system that was both sinking current by driving the GEM control module into constantly trying to monitor and control it. Quiescent current never fell below 2A ... 1000% as would also apply to the S-Type ... and the reason for ongoing battery discharge.

Perhaps it is now a moot point as it appears that Russ has just demonstrated precisely this point, but I do hope this clarification helps other forum members better understand the difference between when the car "appears to be asleep", and when it has indeed achieved it ... if it is drawing >200mA, then it is not "asleep" as defined by JTIS ... and either an inbuilt or aftermarket device or fault is preventing it doing so.

Best wishes,
Ken

 

Thank you for a terrific, thoughtful explanation of the sleep phenomenon, Ken. As an automotive neanderthal, I found your explanation easy to read and simple to understand. Many thanks!
Steve

 

Hi Steve ... Thanks for your kind words, but may I correct two things ...

First, an "automotive neanderthal", you are not. I have seen several of your posts, and by your questions and observations, you reveal yourself with an intelligent, inquiring mind. Moreover, you mark yourself as astute for having chosen such a magnificent vehicle for your carriage. Yes ... it may bite you occasionally, but this is mostly to remind you it needs attention ... and rewards pampering!

Second, and here I stand admonished for relying on my original JTIS manuals, without cross-checking to my May 2011 factory Updates. The quiescent current drain stated as <200mA has been revised to <30mA, as per attached table for all models.

Cheers and best wishes,
Ken

 

I haven't posted in this thread, i believe it was tbird6 you were replying too.

:icon_ wcam:

not forgetting my favourite

 

...from many years as a police detective.

Thankfully, thus far my S-Type has been pure driving joy, no bite yet.

Duly noted. Thanks, Ken.