Hi All
We have a 2000 XJ Sport 3.2 X308.
The rear brake/stop light on the driver side stopped working. Passenger side light comes on, HLSL comes on.
No volts getting to the bulb, If I put 12v on the cluster's connector the bulb lights.
Reading these forum people say it is the SLCM or possibly the BPM. That seems to look like a probable cause from the wiring diagrams which show both lights go back to the SLCM (for some weird reason).

We swapped the SLCM from another 2001 X308 and it made no difference. Swapped the BPM, again no difference. Swapped both together, no difference.
Does anybody have any idea what this could be?

It happened days after the deletion of the small rear boxes that are by the rear axle. Nothing else has changed.

Any advice and pointers would be appreciated.
Thanks

 

read the wiring diagram figure it out. either replacement is burnt or you're running an overlay

 

running an overlay?

Please can you explain?

Wiring diagram shows:
Both rear stop lamps are wired direct back to the SLM.

Workshop manual says:
Page 1921 The stop, reversing and rear fog lamps are controlled by the security and locking module (SLM) which receives inputs via the SCP network from the BPM.

The BPM and SLM monitor the stop lamps (not HMSL) and tail lamps for failure. Fault analysis must be undertaken using the PDU, refer to Diagnosis and Testing.

Which is where I am now stuck. No PDU.

Page 1951 and 1952 Exterior Lighting - Rear Lamp Assembly Bulb only tells you how to change a bulb.

No wire damage visible. Connectors cleaned.

Thanks

 

Anybody have any thoughts before I go buying modules that I do not need?
Thanks

 

Before you buy any SLCM modules (available on eBay), pull the rug aside in the boot (left forward corner) and read the number of the SLCM -- the replacement must match! There are threads on the forum and the XK8 companion that will walk you through it. Stay away from the Youtube that talks you into cross wiring right and left lights. There are also threads which will describe opening the old SLCM and resoldering broken connectors. Not easy, but guys good at fixed computers find it any easy task.

 

Update. OK, after swapping modules between the 2 cars we managed to move the fault to the other car too. Swapped the security module back and the fault moved with that.
Will open her up and check for dry joints and re-solder if needed.

 

Could not find any dry solder joints.
Flowed some fresh leaded solder into the pins that are used for rear lights.
Brake lights seem to go to quiet reed relays on the board. Soldered them too.
I suspect I just need to get a new module.

 

Splice the left side wire that's working fine cut the right side wire that doesn't get power connect them so when you hit brake it will work that's solve it without changing modules

I'm having dilemma with my rear brake lights they're both on brake once ignition on I don't want to touch modules yet
Your problem sounds easy

 

Thought of the day….
Why can’t we just wire in the 2 brake light bulbs in with the 3rd brake light relay? I believe the relay is rated for
30 amps.

 

in my case the 3 stop lamp are stuck on brake all rear left and right and the high mount brake light . He's issue easy fix

 

There is no visible dry joints. But loose pinns in chips and small components.