OK-
Sorry for the long post. I was at the mall today and when I got in the car and turned the key, nothing from the engine at all. The lights and steering wheel worked fine. I also noticed that the power locks stopped working at the same time. You could hear the mechanism working, but none of the plungers went up and down. the key fob armed and disarmed the security system without locking the car. The central lock button did nothing at all. You could manually push down the plungers, which it dosn't normally allow. Also, a few minutes later the windshield wiper started going and wouln't stop. I pulled the fuse for the wipers to get them to stop, then disconnected the battery for a few seconds. When I reconnected the battery, everything was back to normal. does anyone have a guess as to what the problem could be? Seems like maybe the security system got confused and disabled the ignition? Do you all think I should have it in, or is it OK now?

 

I've had some weird electrical gremlins similar to yours... overhead light remained on, alarm wouldn't arm/lock, etc once that a 'soft' reset by disconnecting the battery for a few minutes corrected. I've never had it happen again. Just one of those things.

 

so everyone agrees with H20boy (Thanks, by the way) re: this? I was hoping a tech might chime in here. no problems in a week

 

When the systoms appear 'possessed by a demon', it almost always is a computer problem and the reset will work. Mine occurred after a long battery disconnection due to a stereo system upgrade. My computer was just confused for awhile.

and you're welcome. May those be the only problems you suffer.

 

I had the exact same thing happened to my 1998 XJ8-L. The only thing I could do was to disconnect the battery to resent the computer. Everything seem to be back to normal after disconnecting and reconnecting the battery. Very strange.

 

I'm having the same problem with the security system. I'm at a loss. The car shuts down after driving for a min or less. I only have a hard key! No keyless available. So that being said. I've tried disconecting the negative cable of the battery for a bit and that doesn't work. I've tried putting key in the drivers door unlocking it and putting in the ignition turn 3x and NO! I've had to jump my car to start it.. done that 6x to only stop each one! Now I'm charging the battery! Had car towed! What do I do next! HELP!

 

Try a Hard Reset.

Here is some information summary on a Hard Reset -

I have extracted parts of the infomation from a previous post by forum member Red October:
Disconnect the negative lead from the BATTERY terminal.
Touch the end of the negative lead to the battery positive lead.

Here is a photo that was provided by forum member SuperSport:

NOTICE: NOTHING CONNECTED TO NEGATIVE TERMINAL



Here are a couple of comments by SuperSport:

Remove Negative Battery Terminal from the Negative Battery Post (10mm Wrench)

Touch Negative Terminal End to Positive Terminal End and hold there for 15 'ish seconds (Positive Terminal will still be connected to Positive Battery Post)

Reconnect Negative Battery Terminal back to Negative Battery Post

On First Start after the Hard Reset, let the car idle for a minute or two without touching throttle. This allows the computers to recalculate the throttle position, etc... Also, the car may drive differently for an hour or so while it's relearning your driving habits.

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Next I am paraphasing Red October other comments:

Touching the disconnected negative lead end to the positive terminal will short-circuit the supply rails at the ECU's & modules to discharge the internal capacitors.

Also forum member Reverend Sam comment also helps to explain the hard reset:

When you touch the negative cable to the positive terminal on the battery, there is nothing at all hooked to the negative terminal. Any electricity stored in the electrical system drains out through the negative cable and into the chassis.

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Also here are forum member Brutal comments on hard reset:

The reason I and others say disc (disconnect) the negative (battery cable from the negative post) is 2 reasons
1) it usually the closest and easiest to access

2) there is usually little or nothing else hooked to it
The reason it works on the capacitors is THEY still have a complete circuit on the car so you are giving their positive terminal a path to ground to discharge them.

And since the ignition provides a mechanical link to circuits that are isolated.

You can/should also switch the key to the on position while the battery is unhooked and hard reboot again.

Then shut off the key and go back and reconnect the battery.....and no a hard reboot will not clear codes on ODBII.

While it MIGHT, turn off a check engine light(depending on WHAT, the stored codes are) they DO NOT go away.

There are codes that will only show when active/pending, and if you shut off the ignition they may not show even with Jaguars IDS(again it depends on the code/situation)

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Here is what I have found about how long to hold the negative battery cable to the positive battery cable:
anywhere between 15 to 30 seconds.

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One last comment on Hard Reset found on another website (jeeves and the jaguar.com)
A hard reset is done by touching one of the disconnected battery cables to the other one that is still attached to the battery for about 30 seconds.

This is like doing a full restart and your car will be forced to learn again - you can also temporarily remove stored problem codes this way.
It is normal after disconnecting the battery that you're RPMs will be high when restarting your car and your acceleration will be very brisk.

This is part of the learning process and on your next start up it should be at normal levels.

Jim Lombardi

 

Welcome to the Forum, Sheila.
I've removed your duplicate post on this, it can get confusing to have two threads running.
Hopefully Jim's reset will sort your problem.
Please take time to visit
New Member Area - Intro a MUST - Jaguar Forums - Jaguar Enthusiasts Forum
and introduce yourself so we can all say 'Hello'

 

Had the same issue... Reset the computer via the battery worked

 

Sorry, newbie and don't know how to post. Had my battery disconnected most of the day to replace instrument lights (could find proper bulb on Sunday). Was trying to troubleshoot why bulbs wouldn't work and got called for dinner. Left the key on with batt connected all night. Sorted this out, recharged battery and now no start. I suppose I fried something important/expensive? Kinda clicks like low batt but no crank. Did hard reset, no help. Looks like AAA will be hauling my car to the Jag repair man unless you guys come up with somthing else. Thanks, Barry

 

A lot of these weird problems are from either a low battery, or bad or weak connections to ground points or power points. Not very exotic or glamorous. I had a problem with the braided ground strap that goes from the battery to ground. Car would not start or start with a jump. I took the jumper cables off and the negative terminal was very hot. Moved things around a bit, and car starts. I replaced that with a solid cable. The post at the false bulkhead is another potential area of issues, as is the braided cable under the car fom block (or bellhousing) to frame on right side. I replaced that one with a solid cable too - (maybe I'm a tad OCD).

 

I've had an issue with my car not starting with a fully charged battery. I went to a San Diego independent Jag service and they gave me the "hard Reset" procedure but added doing two locks and two unlocks with the clicker. Haven't tried that one yet but the other hard reset didn't fix my problem.

 

Well got my new instrument panel lights in. Jag part number C2S15074020. List $2.16, I paid net $1.20/each. I did the ground to positive touch for about 15 secs. Did the 2 locks, 2 unlocks with the remote and she started right up. I says low oil pressure, low coolant but think thatS probably from the reset. I'll have to figure that one out now. I am almost a quart low but the coolant over flow res is half full. Big relief for me. And all the panel light are bright. Thanks, Barry

 

So after checking the fluids and talking to my Jag mech, I drove it around, got some gas and setup an appointment to have the check the codes, etc. Went out this morning and the first thing was to recycle the roof. See and earlier post on this. After checking all the codes and clearing issues the low oil pressure, low coolant, etc were still there. They came on after I installed new instrument panel lights and after I did a hard reset to get the car to start. They wanted to check my light installed because that's when this trouble started. OK. So a few minutes later they come back and say its fixed. Altho I got the clips back on the two electric plugs on the panel the black one, left side wasn't seated properly. Still learning. So replacing my own instrument lights and having the car detailed only cost me $360. Duh.

Barry
76XJ6C
2005 XK8