Greetings all.

I am new to the forum and ran a couple searches and could find anything that helped with my problem.

My 2000 XJ8 will intermittantly continue to run when removing the key from the car. Also, with the car sitting without a key and not running, the dashboard will intermittently light up as if I have turned the key to the run position. I get all the alarm lights as if the key were about to turn and start the car. However, it is only the ignition line that is shorting out. When the car is running and removing the key, the radio and other aux systems turn off. This causes significant problems. Besides the obvious issue with the car continuing to run, when the car is parked and it "comes to life" the alarm will go off and headlights will turn on (if set to "auto"). This continues until the battery dies. I am forced to pull the battery ground cable each time I park it. I've given up resetting the clock.

I know it is a wiring problem, beyond the symptoms because (now, don't laugh) I can get the car to "turn off" by slamming the driver door a little harder than normal wear and tear. I can also do it with a slight kick to the lower portion of the steering column. I have replaced the ignition switch, no help. traced out the wiring for the switch as far as I can with no help. I have the JTIS CD and looked through the wiring diagrams and can't find any thing that, if grounded or shorted, would cause this to happen.

If anyone can point me in the right direction as to where to look, I would appreciate it. I am hoping it is not something like the Body Processor Module or some other module, since it has all the symptoms of a loose wire. But everything I can find on the wiring diagrams shows indicator signals leaving these modules, not operating voltages or grounds. I am sure about this, but I can hope. Any help is appreciated.

Cheers,

Andrew

 

There is a relay between the ignition switch and the ECM. Might try swapping with another one and see what happens. Doesn't cost much to try that.

It is the 'stand alone' relay in the right hand side firewall 'extension'.

 

Thanks Mr. Point.

I really appreciate the response. To be clear, are you talking about the Ignition Coil Relay? I'll give it shot with reseating it while looking for a replacement.

Cheers,

Andrew

 

Ok, I opened up the control module enclosure and the ignition coil relay looked like it was sitting ****-eyed in its seat. I swapped it with the A/C Compressor Clutch Relay and left the battery connected. I'll see if it keeps. Thank you, Test Point. I appreciate you getting me in the ball park.

Cheers,

Andrew

 

Well, the ignition coil relay wasn't it. Still having the same problem. I have resorted to installing a battery isolation switch to make it easier to disconnect the ground line when I park it. Still convinced it is a wiring problem. I found a reference about there being two logic ground circuits that must be separated. The note is exactly:

CAUTION: The steering wheel contains two logic ground
circuits that must remain separate. Do not connect or

cross-switch the BO and BK circuits.

This weekend will be spent tearing the dashboard apart trying to fine a broken wire. Joy.

Andrew

 

I suspect this is solely to keep the air bag ground islolated from any noise that might be introduced into the other ground in the steering wheel, used for horn switch, audio and cruise control switches, and perhaps turn signals, wipers, etc.

 

That makes sense.

Thanks.