Tail lights, side marker lights, license plate lights , fog lights are not working
 

I rarely drive this car at night. I just realized that tail, side, fog, and plate lights are not working. Low beam, high beam, brake lights, and hazard are working.

I am lost and do not know here to start diagnosing the cause. All fuses are good.

Please point to the right direction where to start.

1997 XJ6 with 55,000 miles.

See page 82 as the circuit continues on page 80 / 1995 exterior lights are different

The all have the same output from the external lamp module and a common ground stud

http://www.jagrepair.com/images/Auto.../jagxj1997.pdf

Thank you for the link. With the electrical diagrams in hand, I was able to diagnosed that the light module does not received signals for tail, side ,and plate lights from body process module (BPM). I have not determined if the BPM or the light switch circuit short circuited. However, rear fog light switch was working and therefore, I temporally used rear fog light signal to control tail, side , and plate lamps. I also removed the two light bulbs from rear fog lamps and left rear fog lamp switch on at all time. Rear fog lamps work injunction with front low beam. Its only turn on when I turn on low beam.

I will track signal from light switch to BPM as the next course of action.

The manufacture is having a meeting regarding this project. We may have our first aftermarket full led headlights and tail lights very soon.

What I would like is a recreation of the Victory Edition tail-lights but at an affordable price.

Delete

I am sure you already know this but when testing please note that the control feeds to the various modules on the S-type are switched earths not switch live feeds.
In other words the signals for tail, side ,and plate lights from body process module (BPM) are switched to earth when they are 'on' they do not go live with 12v when they are 'on'.

This can get confusing when looking for a fault, but if using a meter when looking for signals between modules, the + lead of the meter needs to be connected to a +12v feed and you need to look for a switched earth.

Mellow

I got lucky. It was a short circuit light switch module and it was not process module nor light module. I got a light switch from junk yard and everything works.