My next door neighbor (older widow woman) has a 2003 XJ8 308 that is having the battery drain. I've read as much as I can find on this forum and am preparing to sleuth the drain source culprit. My Klein DMM with amp clamp is hard to get around each individual wire to each fuse (besides so many fuses 8-o ) so I'm going to do the voltage drop measurement method across each fuse. The only problem I'm having is locating an accurate fuse box layout diagram. Her owner manuals are no where to be found and the fusebox covers don't have the diagrams any longer.

She had a local (non-jag-qualified) shade-tree mechanic do something to the windshield wiper arm so I'm going to focus on the w/w park switch (apparently commom problem) first.

PS: I was a Naval Aviation Electronics Technician who became an Aviation Maintenance Officer after a 30yr career so I believe my electronic and mechanical appitudes are OK.

You folks however are the real PROs so I look to you for mentorship.

 

Welcome spurlockda, we hope members here can be helpful to you and you to us in the future. Please take the time to introduce yourself in the New Members Section under Forums top left, General Jaguar Forums, New Members.

With your knowledge, you'll benefit from this... JagRepair.com - Jaguar Repair Information Resource ...just do a Site Search electrical diagrams. Do a site search here for X308Workshop, its a large file with details on the whole car. Also you may wish to download and look at...

 

I know others on here have their own opinion but, 50ma is what I was taught to be the limit on drain after all the computers go to sleep. If her car has a drain, is the vehicle even driven much? Can you tell us what the ma drain is? Maybe the battery is calcifying and going bad from sitting? Maybe she just needs to get a battery maintainer.

 

I haven't done the main amp drain measurement yet. She just gotdone with an errand so I'm waiting for the 60 minute go-to-sleep period to happen.

Her driving habits vary from driving everyday to it sitting for a few days to it sitting for weeks at a time when she goes on a vacation or something. Her being on vacation was how the problem became onown to me. While she was gone, the car would need jumping after about three days. When I spoke to her about it she said that it has been going on for a while. Really specific details are hard to come by. She states that the battery was replaced within the past 6 months or so by a well meaning friend who is Jag owner also and a non-big brand local auto repair/parts place. Again, accurate details are hard to come by and the local guy didn't punch the date decal on the battery. Thus I have no accurate data to support the age of the battery.

I want to investigate the source of the parasitic drain before I put a battery maintainer band aid on the problem. I'm sure the great folks at Jaguar didn't desigm the car to need a maintainer and further, since she is an older widow woman, expecting her to maintain/employ the maintainer might be a challenge. I know they have solar ones but I'm not ready to go there yet.

Thank you for replying so quickly!

Dave

 

The folks at Jaguar (during X308 manufacturing) also put the best batteries on the planet (IMHO) in these when they were new. I've changed out the original white case Valeo in many of these and they were 10+ years old! Nowadays, it's hit and miss. It's the old adage "they don't makem like they used to."

 

Anytime a Jag (or most any car nowadays) sits for more than a 10 days, a battery tender of whatever brand is highly recommended. With the trickle draw, the battery has no way after a certain time to regain its lost and needed energy to work with the draw. This can also be an issue during start up. So keeping the battery fresh on these cars with a tender chases away a lot of ghosts.

 

"It's the old adage "they don't makem like they used to."" So true!

 

The average quiescent current draw for the X308 is about 30 milliamps.
My 1999 XJ8L can sit for a few weeks and start up fine.

My 2001 XJ8 will drain down to almost NOT starting after a week to 10 days.

Both show to have a 30 milliamp draw at rest.

I disconnect the battery in the 2001 XJ8 if I do not plan to use it for a while.
Someday I might try to figure out why the 2001 does this but I have 5 cars between my wife and I so it is not a priority.

bob

 

Thanks Bob!

I completely understand about setting priorities. I have to keep reminding myself to not fritter away valuable time just because my man-sense says "that'd be cool to mess with this". 5 cars and a wife, hmmmmm Let's see, "Happy Wife-Happy Life!"

If it wasn't for the widow woman, I had an old airplane battery disconnect that I could have used but that too, like the battery maintainer, would have to be elderly-proof ��

30 mA is my benchmark as well based on what I've read here in the various posts.

 

My big challenge right now is getting a really accurate fuse map. One thing that keeps getting me in my initial explorations is the way some of the fuse locations have moved in model-year iterations. Plus, someone (shade-tree guy suspected) has put fuses with the wrong rating in some of the slots?????? ����

 

Reply to post 6: I agree with you. It's kinda sad that the battery technology and the electronics technology can't get synchronized. It's kinda sad that, like you said, most any car these days has to have aftermarket battery-tender support to keep the battery fresh when the parasitic drain demands of the electronics bleeds the life out of it.

 

The fuse map is printed on the fuse lid in the trunk.
There are 5 boxes, 2 in the engine bay, 2 under the rear seat, in the foot well, and the one in the trunk.

I just went through the same.
Besides of checking all one by one, the most common culprit (at least from my research) is the alarm horn battery.
This is a separate battery, they get bad over the years, corrode and start to drain.

If its not that, then yes, check one by one.
You can open all doors / trunk, then push the latches to "lock" the car, then wait 1/2 hr to let it sleep.
This will allow you to work on the inside fuse boxes without waking up the car.

 

The issue for mine is I am constantly out of town for weeks at a time. When I first got the car (04) it didn't seem to affect it, I had a friend starting it every couple weeks and it would slow start. But after a few trips it drained until it killed the battery, even with it being started every 2 wks. Thus killing a cell in it, because it was slightly swollen. I went through my grounds and and found nothing, on my power connections I found the positive terminal wire gaining corrosion and replaced it. When I replaced the battery, I went with a battery tender and haven't had but 1 issue since (replacing the battery to body ground lanyard (in 16), somewhat common to do, caused a dead condition), no corrosion at all and the battery is 8-9 yrs old now. You may want to check that lanyard motorcarman? I found mine when that dead condition happened and I went searching and grabbed it and it was pretty warm....I knew I had found my culprit.

 

For EricJansen post #12: QUOTE=ericjansen;1692724]The fuse map is printed on the fuse lid in the trunk. There are 5 boxes, 2 in the engine bay, 2 under the rear seat, in the foot well, and the one in the trunk.

I just went through the same. Besides of checking all one by one, the most common culprit (at least from my research) is the alarm horn battery. This is a separate battery, they get bad over the years, corrode and start to drain.

Thanks Eric. Unfortunately, as mentioned in my original post #1, I checked all of the fuse box covers ans there are no diagrams in any of them. Also, the Owner Manuals are nowhere to be found.

That's why I'm trying to find some really accurate model year specific fuse box diagrams with fuse amp listings. There are some in there that aren't original and so far I don't trust who's been working on it. She told me that the guys has had to come jump her battery about four times and each time he (or his 'boys') tell her to just drive around for a little while and she'll be good??????? She's way into her 70s I think and I think "Mr Shadetree" was putting her at risk.

 

This should do it, from 4-12 further.
Checking the correct model etc. sat your own risk

 

Bob,
Maybe you should switch the batteries between each of those XJ's and see if they behave differently??



The only MY XJ8/XJR that I know of that has the fuse map printed on the trunk fuse box lid is a 98'.

Somewhere buried deep in this forum is a post where someone mapped out all of the fuse boxes and then took the time to size it to where you can print it out and tape it on the underside of each fuse box lid.

 

Jumping these vehicle with another vehicle or jump box is very bad for them. I've said this many times on here.... I highly recommend a device like an XP-10 micro start (there are many variants and cheaper, but I have this and swear by it), its small, can be kept easily aside (a smaller version will fit in the center council) and even at her age she can handle it. Its also impossible to cross polarize, it has a safety switch to prevent it. Its like putting a new battery in the car and its immediately at full power vs the slow pulsing input wait and see from the others. It holds a charge for an extremely long time. I didn't charge mine for over a year and jumped about 5 other vehicles with it in between and it still had almost a max charge. I just checked mine (it was last charged Dec 2015) and was at max charge still. At that rate it would easily last about 3-4 yrs without recharge and still be able to fire a vehicle. An item like this should give her peace of mind and if she needed help, some back yard Joe couldn't screw up the terminal connections.

 

My car won't start are will randomly die it sat at the dealership for a year and got it only a week ago

 

Well, have you had your battery tested?....could be a dead cell from sitting. Go back to post #2, download and read that pdf I posted.

 

If it is a parasitic drain beyond the limits we can break the whole electrical system down into electrical buses controlled by the king relays . Or if it has a issue with the go to sleep command . This will get you a better AOA on your approach to a successful trap . Do you have any flags on the ADI or HSI ? The X308 wiring schematic is linked below : The actual schematics are in the last half of the Doc . As they have the breakout sheets up front . It can be downloaded by the arrow in the upper right corner . Color code page 16 . Page 31 has the King relays that I'll refer to as buses . Page 36 is the control of the King relays . And page 78 upper left corner as the Key switch ( Key in/ out ) is the command signal to put the security and locking ECU into the shutdown / go to sleep sequence . There is a multiplex bus Doc. if it comes to that as there is one that talks through all the ECU's although you my not have the test equipment to read it .

http://www.jagrepair.com/images/Auto.../jagxj2003.pdf

http://www.jagrepair.com/images/Trai...-JAG_10-08.pdf

Owners Handbook :

http://www.mediafire.com/file/s48q3k...e+Handbook.pdf

Shall we proceed ?

Findings on ignition Switch : Jaguar part # LNA6507BA

By removing connector FC54 9 inches straight forward of switch found ground pin 5 contaminated , cleaned

The pin side of the connector pops off the bracket straight down to be able to hold in free space .

Black wire socket position 5 to ground = 0

.........On the pin side of the connector :

Black wire pin position 5 to pin 1 key position 2 = 50 ohms Run position

Black wire pin position 5 to pin 2 key position 1 and 2 = 0 ohms Acc position

Black wire pin position 5 to pin 3 key position 3 = 30 ohms and bad large waver as moving key radially ( needs replacing later ) Starter

Black wire pin position 5 to pin 4 key insert = o ohms , key removal = open ohms this is the security ECU input

http://www.ebay.com/itm/1995-96-97-J...EAAOxywOtSXf2r