in the information window of the speedometer. Nothing shows to be amiss during the system check at key-on. But sometimes after about 5 minutes of driving, from cold start, I get these two messages: Check Rear Lights and Cruise Control Unavailable. When I look there is nothing wrong with the rear lights. Cruise is however not available. It doesn't do it every day or trip. Any thoughts or similar experience?
Sometimes a dying battery can cause gremlins and I think the battery may be original (36000 miles, 2004 XK8).

Ken

 

No first hand experance but from what I've read on this forum the problem you describe is often caused by a faulty brake light switch.

 

Yep, that's the symptom all right.

There are actually two physical switches inside the assembly. One is the brake lights, the other is the cruise disable. What you are seeing is probably an intermittent cruise disable switch, so the lights work as normal but every once in a while the ECU gets an intermittent signal from the other side.

 

+1 on the brake light switch. I have this problem at the moment and am awaiting a delivery of enthusiasm to get it changed.

 

I had the same thing...was the brake light switch on my 2005 XKR Coupe.

 

Gus' instructions for replacement: JagRepair.com - Jaguar Repair Information Resource

 

Replacing the brake pedal switch goes much easier with two people. The smaller person works on their back underneath the dash while the larger person guides the new switch assembly into place from the engine bay. Remove the drivers seat for much easier access while working in the floorboard. Good luck....

 

Wow .... thanks for the quick response guys! You're explanations make perfect sense for the symptoms I observed. And I appreciate the fix-it link. Every little bit helps with these beautiful cars.

Ken

 

i have the same errors, and cant wait to get the new switch

 

I did mine to fix that issue but I used the new switch and mounted it to the original bracket. Just Loosen upper nut on the bracket remove the lower one. Remove switch.Then bend the bracket over to the right. Installed new switch and while holding the brake pedal down, (engine running) I bent it back to engage the lever on the brake pedal. No need for 2 sober people!

 

Will tackle this as soon as the motor mounts are done on the car, glad to know I won't be needing to enlist help! This is the last error code I have to banish, and then she's all ready for a nice long road trip.

 

Grantorino62, did you remove the driver's seat when installing the new switch onto the old bracket? Thanks in advance...

 

Nope! I'm 5'10" 200 lb so I just straddled the top of the seat with legs on either side of the headrest. I was able to just remove the nut off the lower stud holding the switch. Once off, I rotated the upper bracket nut 2 turns. Slid the new switch onto the bracket and tighted the lower nut on the stud. Bent the bracket back in line with the pin on the brake pedal, car running so the pedal went further down.