To start, I know this is a common issue on the X300s and I've looked at the countless threads in the X300 forum here about this topic. I have symptoms that don't quite match any of the threads I've seen posted here about this issue.

• What works:
  • When I use the key to lock and unlock the car, the door locks do respond automatically
  • If I'm in the car and I push down on the lock indicator post on the driver's door to lock the car (or pull up to unlock), the other doors respond automatically
  • If I exit the car from the driver's seat, all the doors unlock when I pull the door release handle

• What doesn't work:
  • The boot release button on the outside of the boot lid (the fascia button with the jaguar emblem) doesn't work, regardless of whether the car is locked or unlocked
  • The boot release button on the dash doesn't work, regardless of whether the car is locked or unlocked
  • The "lock" button in the center control stack next to the clock doesn't work
  • When using my key fob, the headlights flash to indicate that the signal is received, but the locks don't respond to the signal
  • The fuel filler flap will lock automatically with the rest of the doors but will not unlock automatically with them

I have inspected the wiring that runs along the right-hand trunk hinge, all looks good here. I have the electrical guide for the car, and I believe I've checked all the relevant relays and fuses, but I suppose I could be missing one or more.

At this point I think I've either got a bad Security Module/SLCM (the one in the trunk under the fuel filler area), or maybe I'm stuck in valet mode. I don't think it's valet mode though because I am able to use the key to open the trunk, and the trunk lights and "trunk open" dash indicator light come on, which I understand is one way to cancel valet mode. At one point I removed the SLCM and opened it up to inspect the PCB, but nothing looked out of the ordinary and I reinstalled it. At this point the only thing I can think to do is replace the SLCM. Thoughts?

 

Hello Eric!

I wouldn't replace the SLCM just yet. They don't seem to fail too often. It would likely be a waste.

It's always good to have at least a few things that work. Sounds like the door mechanisms are ok.

Ideas:
Have you disconnected the battery and touched the cables together for a few seconds? That's known as a Hard Reset. It might help.
Have you followed the key fob programming steps to be sure it is programmed correctly?
When the trunk is closed, is the "trunk open" indicator on the dash off (extinguished)? There is an important switch on the trunk latch that is integrated into different functions.
You could probably test the trunk push button (and latch switch) for functionality fairly easily. Wouldn't hurt. Also to check continuity of the wiring in there..

More ideas forthcoming, from myself and others.

 

Hey there Richard; appreciate the response.

I have had the battery disconnected many times before, but never touched the cables together for a "hard reset" as you describe. What effect does touching the cables together have that doesn't come about just by disconnecting the battery? I understand that it would bring the positive and negative ends of the electrical system to the same voltage, but it seems like nothing additional would happen here because the system wouldn't be powered.

I have attempted to program the key fob before, but I have never been able to get the car into "pairing mode". I cycle the valet switch 5 times, but I never get the beep or the headlight flash to signal that pairing mode is active. I have also tried pressing the valet switch fast, slow, more than 5 times, etc as recommended in other threads where people can't get the car into pairing mode. Seems like the fob is correctly paired to the car though, since the headlights flash when I press the buttons on the fob. Is it possible for this to happen if the fob isn't properly paired to the car?

The "trunk open" dash indicator light works properly, illuminated when trunk is open and not illuminated when the trunk is closed.

A few years ago I did do some investigation of the electrics in the trunk lid. My memory is foggy on this, but I believe I did some quick continuity checks with a multimeter. I also remember that I removed the electric trunk actuator and connected it to power outside of the car, and it worked fine. I also have an extra actuator that I snagged from an XJ at Pick-n-Pull a few years ago, so I can replace it if this turns out to be the issue, but I doubt it.

 

Hard Reset can help to eliminate electrical gremlins. It brings stored energies back to zero (i.e. memory capacitors in different modules). Some people have reported good results from doing this, but proof of its healing powers is somewhat cloudy to me.

Opening the trunk is the first step to key fob programming. Then open the driver's door, turn the ignition on, and rock the valet switch 5 times. Fob programming is one thing the trunk latch switch enables. But seems as if yours is working correctly. I don't think the headlights would respond if the fob isn't programmed correctly. That is a mystery.

The dash console door lock button only works if the key is in position 2 or 3 (one click or two). Unless something's wrong!

There are a handful of fuses to be checked too. You probably already did that. How about checking connections at the sounder at the right front fender too.

It would be nice to "try" a different SLCM, but there is that risk of throwing parts at a problem and missing.

 

 

Tried the hard reset, no dice. Also re-checked the fuse (blue 15A) and the relay (black with violet stripe) for the trunk actuator, and both seem fine.

 

I had a similiar problem... found 2 wires broken at boot hinge (a black one and an orange one). Resoldered and boot button works again.
If I was you I'd take out the plastic wrap near the boot hinge and follow the wires as far as you can.
Earlier this year I found a wire rubbing against the gas tank nearby that had missing insulation, creating a short. This caused a different problem (possible battery drain and low fuel-pump current).