I did a recent post regarding a warning light that said "cruise not available/check rear lights". Received much helpful feedback indicating that the problem was with the brake light switch; appreciate all the replies.

However, after confirming that the problem could not be anything else other than the switch, another situation has raised doubts as to whether there is another culprit lurking. Example: went out for a ride yesterday, drove for 10-20 minutes to run and errand; no warning light. Along the way, I set the cruise control, got the message "cruise activated" and it worked fine. Drove a ways, cancelled cruise (got message confirming cancellation) and continued on my way. Stopped the car for 15 minutes, went back out and drove again for another 10 minutes, no warning light, arrived at second stop. About 20 minutes later, started the car and resumed final leg of my journey....no warning light. Tested the cruise control again and it worked fine....no issues. (BTW, all rear lights are working as required). Continued back home, no warning, pulled in garage, and warning light came on!! Turned car off, restarted immediately...no warning light!!!

Is there something else going on here?? If the switch is bad, wouldn't the warning light be on all the time??

As usual, would appreciate any helpful hints from Forum members.

Thanks

BTW, this is 2006 XK8, carbon fiber edition, 111K miles

 

One would think, but they seem to stop switching reliably instead. They start by failing once in a while, then more frequently, then sometimes not at all for a while. And then more when it is hot. Except on Thursdays in the northern hemisphere. Some have had success re-doing the solder joints without really replacing anything. Others have replaced the switches themselves (involving new soldering of course). Most just replace the part after shopping on price for a while. Unless done several times, the part is a pain to put back in place, so most try and do the job once.

 

As mentioned above, the brake pedal switch typically starts as an intermittent failure that gradually gets worse as time passes. I have had good success having the two microswitches in the assembly replaced with better-quality units and having the circuit board solder points made more robust at the same time....

 

Thanks for the tips. I ordered a new switch and was told that it is on backorder...availability TBD. Don't really drive the car that much, and winter is coming, and we're off to FL in 2 1/2 months (car stays in MI), so maybe I'll just wait until part becomes available and replace switch in the spring...!!!

 

Same deal. Replaced the switch on my 01 XKR. Fixed the problem. But every tiime I bench test the old one it works perfectly? Soldered copper wires to the top of studs after inserting from the top. Pulled switch into place, slid nuts down wires. cut wires off. I may have gotten info from a post here.

 

12 years old, 111000 miles......I think I'm just going to spend the extra bucks and get e completely new switch...….old one out, new one in...done!!

Thanks

 

Save the old one, someone may want to repair it for a spare. The microswitches are less than $10.

 

Thanks....good idea. (Maybe I'll just clean it up, send it back, say it didn't work, and get a refund.....!!!! Nah, that will never work)

 

Unfortunately, you're close to the truth. A couple members have reported early failure of replacement switches.

 

Not encouraging......do you have any idea where they got the switches???