I decided to start a new thread on this topic since I felt like I was hijacking the RP thread (see https://www.jaguarforums.com/forum/x...ce-help-36278/ for the full discussion) and wanted to get a new start on this issue here.

Background -- I have been experiencing a Failsafe Engine Mode message with my cruise control switch turning off at the same time. A search of this site leads me to believe that I might have a bad brake switch, but the information that I found was about replacing the switch on the XK8. I looked for a replacement switch on the 'net and found that the one I need is quite different than the XK8 switch (if I'm wrong about this, please correct me). I then looked in my PDF version of the repair manual for the X308 and found the replacement procedure, and in the illustration it appears that I am correct about the switch I need.

So, here are some photos -- the first one was taken under my dash. It is the connector that goes into the brake pedal position switch. The other two are the 2 pages from the repair manual that shows the removal/installation procedure.






Ok, now that I have that out of the way, let me ask a couple questions specifically about the XJ8.

1. Has anyone ever replaced the brake switch that I have pictured above? If so, is the procedure to simply remove the plug, and unscrew the one little nut? That seems pretty simple.

2. Has anyone ever fixed the Failsafe Engine Mode issue that is accompanied by the cruise control being disabled by replacing this switch? If so, I'm open to any comments, etc. about this issue.

3. I don't like to spend any more money than I have to, but I don't want to buy a piece of crap part. With that in mind, where would you recommend I get the switch, and do I need any other parts as well? If you have the part number, that would be handy as well. This is my ONLY car, so I always have to make sure I have all my bases covered and all my parts in-hand before beginning to disassemble anything!

Thanks! I look forward to hearing from all of you!!!

Mike

 

Your part number is LNB6420BB , try the bellow link Brake Pedal Housing-Automatic - Parts For XJ Series from (V)812317 to (V)F59525 (X308) | Jaguar Classic Parts UK
It is good as a part search database. Try to google the part number and you can find a few shops selling it.

 

Yes, your description is all it takes - but the nut is in a tight spot and you must hold the bolt from turning too - it just requires some patience and the ability to stay upside down under the dash for a long time... and a ratcheting box wrench helps!

 

Thanks for the part number, that was the one I was looking at. Sure seems a lot easier than the XK switch, but a lot more expensive! I'll get one on order here soon and will post photos.

 

I took the easy way out and just emailed my parts contact person at Welsh Enterprises and ordered the switch -- it'll be here in a few days. Will update this thread when I get it.

BTW I have been driving my car for two days now without getting the FS message -- could it be simply because I turned off the master switch for the cruise control? Or am I just lucky? And if it's because I have CC turned off, does that indicate that it's the BPP switch or maybe it's the CC switch? Either way, I'll be replacing the BPP switch when it comes in.

 

Third day of driving with the CC master turned off and no errors -- wish I had known that it was just that easy to fix this problem! LOL

 

My 98 would do that. So I did same thing. My 99 keeps blowing the fuse. So I'm having to hopefully replace the switch.

 

I've completed four days of driving without any amber messages! How nice is that? I've driven over 200 miles in those four days. Can't wait to get the new switch so I can use the CC again - I'm a CC addict, I use it all the time. Cruise Control keeps me from getting speeding tickets! I found myself doing nearly triple digits the other morning on the way to work -- not a good idea on I-95, but the traffic was moving along nicely and I was just happy to be driving my XJ8!!!!

 

Looks like you found the problem.

 

Yes, Gus, I believe so...thanks to you and others. Only time will tell. I'm looking forward to getting my new switch installed.

 

Got the new switch today -- now I have to find time to install it. I'll take photos.

 

Ok, finally got it installed! The nut was really difficult to get off since I only had one wrench that would fit on the nut, and had to use a vise grip to hold the bolt -- took a lot of trial and error. Getting the nut back on was another issue -- holding the brake pedal down while holding the vise grips and using the one wrench on the nut (thank goodness it was a ratcheting wrench) finally did the trick.

Here's a photo of the switch after unplugging the wiring harness. You can clearly see the nut and the bolt that had to be manipulated.

Also, getting the switch into the correct position before tightening the nut wasn't too bad, but took a little perseverance since I couldn't see what I was trying to get the top end of the switch attached to, but it finally slid into place and seems to be sitting just right.

The old switch looks fine and seems to work. Only time will tell if this was the fix I needed. I took a short test drive and used my cruise control without issue. I'll report back if I get the error again.

Thanks a million to all the helpers on this site -- $85 and a little sweating was all it took. Can't even begin to imagine what the dealership would've told me the problem was and how much they would've charged!

 

Just hope this doesn't jinx the fix, but I've put about 200 miles on my car with the CC master switch on, and even used CC a bit, with no problems. Apparently this was exactly what the doctor ordered - I'm now onto other projects like replacing the upper shock mount bushings and trying to take out the driver's seat to see if I can fix the airbag light issue.

Thanks!!!!