I have a 1998 Jaguar XJ8L. Like many others, I have electrical issues that exhibit the following symptoms; no running lights, no tag lights, no side markers, no front fogs and the instrument panel dimmer control doesn't seem to have any effect on the interior lights. I still have low beam and high beam headlights, rear fogs, brake lights, trunk lights and interior lights. When I tied the side markers to the rear fogs, they worked when I turned on the rear fogs. The tag lights used to work, but stopped working recently.

After doing a search of this forum for similar problems, I followed the advice from several of the resulting threads. I have tested all of the fuses in the trunk, engine compartment and left and right heelboard blocks. They were all good . I have tested the ground connections throughout the trunk and they were good. I have tested a few of the key relays in the trunk fuse box, and they were also good. I also tested the wire bundle under the right trunk hinge. There was no noticable indication of damage when I tested for breaks. I had the lights on when I did this and there was no change in lights when I played with this bundle.

I am down to the switch in the steering column stalk, security module and body processor module. The only issue with my security system is a weak alarm sounder. It's more like a mouse squeak than a proper alarm sounder. I am changing out my clockspring to fix an airbag light this weekend and will check the steering column stalk switch wiring then.

After looking at the schematics, all of the affected systems seem to point to a bad BPM. I am hesitant to purchase a replacement without having a solid diagnosis of the problem. Are there tests that I can perform on the BPM that will tell me whether it's good or bad?

Thanks for any suggestions that you might have.

 

Hi Chip, we would greatly appreciate if you'd introduce yourself and you Jag here.... https://www.jaguarforums.com/forum/n...-intro-must-5/ ....it is a site requirement to do such.

You obviously have been chasing a ghost. If you cannot determine your issue, I can recommend an inde' over on Forsyth. Andy is a pretty good tech. Btw...I live on the East side of town.

 

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Done!!

I am in the Four Corners area. ​​​​​​I have taken my cat to Andy for a couple of things. And this will be one of them if I can't figure it out. I have a few things to try yet. I try to do the work where, and when I can.

 

 

Cool, maybe we could meet up at Mission BBQ sometime? I'm up north at the moment, I'll be in Windsor, Conn Tues and maybe heading back down after that. I may run over to Sturbridge, Mass first for BT's BBQ...does it seem like I like BBQ?