Hi guys,
I still have the same car as before but I need to ask a question about it with no extra clues given. If I get any replies asking questions, I'll be happy to answer those that I am able.
So, imagine the situation. There is a 1995 Jaguar XJ6 with a brand new, Yuasu Pro heavy duty battery. The battery has been fully charged using an external battery charger (also virtually brand new). There is no drain on the battery other than the standard Jaguar alarm system. All of the doors, boot/trunk, windows and bonnet are closed and the alarm has been set. Those are the simple facts.
The question is, how long do you think that the car can be left to stand before all power is drained from the battery? When I say, "drained" I mean leaving not enough power to make the courtesy lights come on when the door is opened.
I don't expect answers down to the last 3 minutes but 2 weeks either way would be excellent and a month plus or minus would give me a working figure to play with.
Many thanks for any help with this,
Steve

ps .... I need to shut down the PC now but I'll keep checking as time goes by.

 

Hah, your up there, things happen differently to my REAL WORLD.

At a guess, about as accurate as "how long is a peice of string".

My XJ-S left for 6 weeks (we were in Vegas) and NO alarm or other rubbish, started just fine, ALTHOUGH there was a noticed sluggishness to the activity due to some drain on teh battery. It was left connected coz I FORGOT.

The X300 was left for 4 weeks, in the shed, UNLOCKED, so NO alarm activity, and started just fine.

The S2 XJ12, 3 days, NO WAY.

The MK10, well, being a redhead female, anyones guess on any day would be just fine, sometimes the beast fires straight up, others, stays home and sulks, life goes on.

I have generally disconnected the battery on any that will stand for more than 4 weeks without use, however, I now have a "battery minder", and it is connected to the S Type whilst not being used, and just keeps the battery "topped up", saves me messing with radio codes and other hi-tech stuff.

I would imagine 8 weeks should see the car start sort of OK, but after that, simply dunno.

Most battery manufacturers claim a battery has a shelf life (in a retailers shop) of about 90 days, and then begins to sulphate up, so disconnected, and fully charged, should see you OK for about that time frame.

 

Steve,

Whilst I can't say how long to drain the battery, I can tell you the longest my 1996 XJ 3.2 Sport stood locked and alarmed was six weeks. At the end of that period, it started straightaway.

So from my experience with the same model fitted with an OE Jaguar battery, the answer must be definitely longer than six weeks and the ease with which mine started would suggest considerably longer.

Graham

 

I can't say for the XJ6 but my XK8 sat from the end of May to the end of September with no problems.
Are you still having battery troubles?

 

Ahhhh, I knew this would happen.
You guys are giving times from leaving the car to it being able to start but what I need is the time from leaving the car to no power AT ALL.
The question that I can easily answer was "Are you still having battery problems" and the answer is a simple "Yes". The car battery was charged and then the car sat on our drive for about 6 weeks without being used. I'm disabled and the hospital gave me a body brace contraption which meant that I could get out and about but I couldn't drive so we used my wife's Citroen. Then we went on holiday to, surprise, surprise, Las Vegas. You should have seen the fuss caused by the body brace at all the airports but luckily I was in a wheelchair and had Airport Assistance where an airport rep takes you through all the security stuff.
So anyway, we got home and I felt a bit more mobile so I went out to the car. The first thing that I noticed was that the alarm didn't beep at me. Then I noticed that the door light wasn't lit. I tried to fire her up but she was as dead as a do-do. I've taken the battery out and had it on charge for 2 days now hoping to try again when this rain stops.
Cheers,
Steve

 

Steve,

Much clearer now.

Most of these draw about 0.5amps for all the memory items, such as radio, and alarm, and maybe some for the various ECU's in the car.

6 weeks sounds a little too short to me. It would possibly be down a bit, but dead, mmm, not in my thoughts.

The only true way to sort this would be to attach a digital amp meter between the disconnected -ve battery lead and the -ve battery post, and actually observe what is being drawn when the car is put to sleep. Obviously you will need to close the boot, so a pair of longer leads to the exterior will be required.

I did this with the XJ-S a long time ago, and yes I was having battery drain issues, and found 2.75amp draw when "asleep". The main issue was a leaking diode in the alternator, and it did take some serious finding. The other was the OE stereo memory. Once sorted it read 0.27/8amps.

I too have airport issues, too much metal inside the torso. Fun is had mostly.

 

Grant ..... I don't suppose you will remember but I had the car in the shop for a related incident and they changed the alternator, or at least sent mine away and had it refurbished.
I sometimes wish that cars could go back to the days before all the trickery-pokery that they have now. Do you remember the earliest form of car alarm? It was a cap gun set to fire when the door was opened by means of a bit of string. It didn't drain the battery and never failed to go off. The only downside was that it cost you a cap every time you opened the door with the alarm set 'cos there was no way to switch it off, lol
Cheers,
Steve

 

Steve,

Yep it is drifting back to the memory cells now.

The dead flat after 6 weeks, with supposedly only the alarm monitoring the car, and the memory of the stereo, and digital clock taking current from the battery, is a tad overboard.

A continual process of elimination will be the only way of tracking this down.

The simplest, in my opinion, is to disconnect the battery and let time tell the story, but sadly, the alarm will not be taking care of the car, and you still will be none the wiser as to what is draining the system.

Soooooo, putting a digital amp meter between the battery post and the disconnected lead, and read the amp draw, then arm the car alarm, and note that reading. Most digital amp meters have a max load of 10amps, which will be sufficient to do this test, but switching ON lights etc will overload it.

Some cars I have dealt with have had an issue with the antenna drawing current, even though it is deemed to be "off" ??.

Sadly the alarm systems, whether factory, or aftermarket do also cause this drain issue.

The X300 also has a documented issue with the central locking motors in the doors shorting, mainly the drivers door. Most of these concerns have been in the USA cars, but same system on ours.

The other thing that has LIVE 12v is the relay pack that controls the thermo fans, maybe something there is having a hissy. I say that coz recently due to our hotter weather, my fans will start up some minutes after shutdown due to heat soak, so I know for sure they are 12v live supplied. Not saying your fans are actually running, but maybe a current draw via the relay pack is happening??.

The reading from this amp meter test will tell all very quickly.

 

Yep, Stevie. You need to measure the current draw after about 15 or 20 minutes. It should be about 30 -35 ma. (the trunk light should have shut off by then, I believe). If it is higher, then you will have a little detective work to do to determine the root cause. I'mbetting the key switch side to sid emotion that activates the security system in the ROW cars.

 

I have a '95 XJ6 and a '96 VDP. I gave up trying to figure out about battery drain and such and just bought a Battery Tender to hook to whichever car I'm not driving at the moment. Hooked a quick disconnect to both cars. Now no worries.

 

I just bought a 1997 Jaguar XJ6 from the original owner and it sat in her garage under a cover for 5 months after her husband died when i bought it. And it didnt need a jump or nothing....i was lucky it ran so good on the start up

 

mine sat in the garage, unlock with a 3 year old battery, and a battery tender from late October until 2 weeks ago. Fired right up and went into service for 3-4 days.

 

It might depend upon what battery you have in the car as well. If I recall, the boot floor is drilled for 3 different positions to accept different sized batteries for different markets.

I had a Canadian market VDP with the largest battery and it was huge. I think it weighed over 60 lbs and 14" long.

 

I've jinxed myself. After a new battery and alternator, I have a flat battery after just a couple days. Time to dig out the DMM and start pulling fuses.

Any hints as to which fuses to start with - other than the ones that are easy to get to?