XK8 / XKR ( X100 ) 1996 - 2006

Brake Light Switch

 
  #1  
Old 05-04-2015, 07:21 AM
Senior Member
Thread Starter
Join Date: Jul 2014
Posts: 283
Received 34 Likes on 24 Posts
Default Brake Light Switch

Hello,

Saturday, I started getting "Check Rear Lights/Cruise Control Not Available" errors.

I am thinking the Brake Light Switch went bad.

On the XKR, is replacing the switch the same as in the XK8?

I have a link here posted by Gus on 1/1/12.
JagRepair.com - Jaguar Repair Information Resource

Thanks,
 
  #2  
Old 05-04-2015, 07:35 AM
Veteran Member
Join Date: Jan 2009
Location: Raleigh, NC
Posts: 9,836
Received 2,080 Likes on 1,583 Posts
Default

I would guess that the procedure is exactly the same. Hopefully some R owners will chime in and confirm....
 
The following users liked this post:
R3Wood (05-04-2015)
  #3  
Old 05-05-2015, 12:42 AM
woox4's Avatar
Senior Member
Join Date: Aug 2012
Location: Tauranga, New Zealand
Posts: 546
Received 211 Likes on 163 Posts
Default

Sure is, exactly the same.
 
The following users liked this post:
R3Wood (05-05-2015)
  #4  
Old 05-05-2015, 05:18 AM
stevee D's Avatar
Member
Join Date: Jun 2014
Location: florida, usa
Posts: 43
Received 11 Likes on 6 Posts
Default

I had the same problem with the brake light and went to the junk yard. Found an old jag with the same type of switch, but the pigtail was a little shorter. Just did a little solder job and exchanged the pigtails. Cost $5 instead of the $197 at the dealers. Also found that the problem was one of the two little micro switches inside the switch. This would also be a very easy fix with a solder gun. Hope this helps.
 
The following users liked this post:
R3Wood (05-05-2015)
  #5  
Old 05-05-2015, 06:01 AM
Senior Member
Thread Starter
Join Date: Jul 2014
Posts: 283
Received 34 Likes on 24 Posts
Default

Thank you. I will get on this right after I change out the front struts and fix the A/C. I appreciate the replies.

Thanks!
 
  #6  
Old 05-05-2015, 07:49 AM
fmertz's Avatar
Veteran Member
Join Date: Nov 2014
Location: Eastern USA
Posts: 1,694
Received 779 Likes on 608 Posts
Default Zero Dollar Fix

FWIW, I went in the other direction. I removed the switch from the car, and took a hard look. There was no obvious sign of bad solder on the pigtail, or anything wrong with the switches themselves. The issue was that the plastic cam that was activated by the brake pedal was worn unevenly and caused the switches to click separately. My understanding is that these switches are supposed to be opposite of one another (one closed, the other one open) at all times, and are built to that effect (one is NO, the other one is NC). When the cam causes one switch to click early in the travel, both switches are in effect at the same state, the computer detects it and throws the error. For now, I ended up propping up the "low" side of the cam with a thin strip of electrical tape, all the while making sure the switches were clicking together. It has been over a week since the repair and the issue has not come back (daily driver), so I am pretty confident in the diagnostic. As to the repair, I am pretty sure the issue will come back once the tape slips, wears out or otherwise stops serving its function. For a more permanent repair, maybe a few layers of glue would do, or alternatively, maybe shaving the "high" side would be easier. Best of luck, keep us posted.
 
The following users liked this post:
R3Wood (05-05-2015)
  #7  
Old 05-06-2015, 10:50 AM
Senior Member
Thread Starter
Join Date: Jul 2014
Posts: 283
Received 34 Likes on 24 Posts
Default

One last question on this. Can you do it without removing the seat?
 
  #8  
Old 05-06-2015, 11:23 AM
Veteran Member
Join Date: Jan 2009
Location: Raleigh, NC
Posts: 9,836
Received 2,080 Likes on 1,583 Posts
Default

Yes, if you are less than five feet tall, an experienced circus contortionist, and have the hands of a five-year-old Chinese girl....


Pull the seat. The job will be significantly more comfortable and you may not exhaust your full vocabulary of curse words....
 
The following users liked this post:
R3Wood (05-06-2015)
  #9  
Old 05-06-2015, 11:38 AM
Senior Member
Thread Starter
Join Date: Jul 2014
Posts: 283
Received 34 Likes on 24 Posts
Default

Originally Posted by Jon89 View Post
Yes, if you are less than five feet tall, an experienced circus contortionist, and have the hands of a five-year-old Chinese girl....


Pull the seat. The job will be significantly more comfortable and you may not exhaust your full vocabulary of curse words....
Thanks .
 
  #10  
Old 05-06-2015, 11:40 AM
fmertz's Avatar
Veteran Member
Join Date: Nov 2014
Location: Eastern USA
Posts: 1,694
Received 779 Likes on 608 Posts
Default

Originally Posted by R3Wood View Post
One last question on this. Can you do it without removing the seat?
I left the seat in place, and it is not entirely comfortable. Altogether, I would say it is more frustrating than difficult. I am about average build.

One more thing. You can remove the bracket with the switch on it by removing the 2 nuts next to the brake booster, or you can remove the switch off the bracket, and leave the bracket in place. If you take the latter approach, only the bottom nut needs to be removed. No need to mess with the top nut as it puts no pressure on the switch itself.

Note to self: Take more pictures!
 
The following users liked this post:
R3Wood (05-06-2015)
  #11  
Old 05-06-2015, 11:46 AM
Senior Member
Thread Starter
Join Date: Jul 2014
Posts: 283
Received 34 Likes on 24 Posts
Default

Thanks.

I'm thinking, my son is 11, 12 in June. I have taught him a few things, he replaced the battery in my wife's Lexus with supervision, and helped me with the brake job. On the battery, he did everything except lifting the battery in place.

Maybe I can get a look at it, un-bolt from engine bay and send him under there to put in the new one.
 
  #12  
Old 05-06-2015, 02:02 PM
Veteran Member
Join Date: Jan 2009
Location: Raleigh, NC
Posts: 9,836
Received 2,080 Likes on 1,583 Posts
Default

That is indeed your best shot. Let your son do the install work from the floor of the cabin while you guide the two bolt posts through their holes from underneath the hood. This job goes so much easier when you have two people doing it. When we replaced the brake pedal switch assembly on my wife's XK8 in October 2012, she was on her back in the floorboard pushing the new switch up into the firewall while I was underneath the hood pulling the switch's bolt posts through their respective holes via the monofilament fishing line I had tied to them to make the entire process easier for both of us....
 
The following 2 users liked this post by Jon89:
R3Wood (05-07-2015), stetson1 (05-12-2015)
  #13  
Old 05-07-2015, 07:22 AM
Veteran Member
Join Date: Aug 2013
Location: Poughkeepsie NY
Posts: 1,031
Received 268 Likes on 238 Posts
Default

Originally Posted by Jon89 View Post
That is indeed your best shot. Let your son do the install work from the floor of the cabin while you guide the two bolt posts through their holes from underneath the hood. This job goes so much easier when you have two people doing it. When we replaced the brake pedal switch assembly on my wife's XK8 in October 2012, she was on her back in the floorboard pushing the new switch up into the firewall while I was underneath the hood pulling the switch's bolt posts through their respective holes via the monofilament fishing line I had tied to them to make the entire process easier for both of us....
I hope she charged you the daily rate Jon / and no discounts for child labor they work just as hard ! Good luck!
 
  #14  
Old 05-07-2015, 07:35 AM
Senior Member
Thread Starter
Join Date: Jul 2014
Posts: 283
Received 34 Likes on 24 Posts
Default

Originally Posted by jamdmyers View Post
I hope she charged you the daily rate Jon / and no discounts for child labor they work just as hard ! Good luck!
Nice
 
  #15  
Old 05-07-2015, 08:25 AM
Veteran Member
Join Date: Jan 2009
Location: Raleigh, NC
Posts: 9,836
Received 2,080 Likes on 1,583 Posts
Default

Hey, it's her freakin' car, not mine. She'd better help if she knows what's good for her (and no whining about it, either)....
 
  #16  
Old 05-12-2015, 07:26 PM
stetson1's Avatar
Senior Member
Join Date: Dec 2013
Location: Central florida
Posts: 334
Received 32 Likes on 27 Posts
Default

I bought my '99 xk8 back in '09 with 36k and the switch was my first necessary repair. found a good indy shop in town that works on Jags and they took the car in at 8am and said I could pick it up at around 1-2pm.


They didn't get it done until the next day, late in the afternoon. I forgot to ask em if they took the seat out but because of the lengthy amount of time to actually complete the r&r, i'm assuming they didn't.


they billed me $90 and I was relieved!
 
  #17  
Old 05-13-2015, 11:01 PM
Senior Member
Join Date: Nov 2011
Location: Stamford CT USA
Posts: 657
Received 90 Likes on 75 Posts
Default

For $90 I'd get mine fixed tomorrow! I am currently living with no cruise control (I do have brake lights) because I just can't bear the thought of lying on my back, poking around under the dash. Unless he's done it before, I don't imagine any mechanic would realize what he's getting into by accepting the job. The bill could be a shocker.
I recently took my XK8 to a Connecticut repair shop for emissions testing and before I said anything, the mechanic got a sort of panicky look on his face and almost yelled at me, "We don't work on Jags." He was relieved when I explained I was just there for emissions.
 
  #18  
Old 06-04-2015, 11:32 AM
Junior Member
Join Date: Jun 2015
Posts: 1
Likes: 0
Received 0 Likes on 0 Posts
Default brake switch

Originally Posted by R3Wood View Post
Thanks.

I'm thinking, my son is 11, 12 in June. I have taught him a few things, he replaced the battery in my wife's Lexus with supervision, and helped me with the brake job. On the battery, he did everything except lifting the battery in place.

Maye I can get a look at it, un-bolt from engine bay and send him under there to put in the new one.
try wd40 first I managed to get the red tube into the switch were the brake pedal touches and gave it a good blast from a new can it didn't work straight away but after a 15 min journey restarted engine warning light went out its been okay for the last few days
 
  #19  
Old 06-04-2015, 04:28 PM
Member
Join Date: Jun 2015
Location: Knoxville, TN
Posts: 59
Likes: 0
Received 21 Likes on 13 Posts
Default "Flashing" the brake light switch

Somewhere someone posted that he powered a standard automotive bulb through the cruise part of the brake light switch and cured his "chk rear lts/cruise N/A" error message. I tried it and sure enough, it cured the problem. Many thanks to that guy! Measure the resistance of the cruise part of the switch - should be about 0 ohms with pedal up, infinite with pedal pressed. Mine (and this other fellow's) read anywhere from 5 ohms to hundreds or k-ohms or even open with the pedal up. So I pulled a fuse, found a source of key-off battery voltage, connected to one side of the bulb, connected the other side of the bulb to one of the switch leads, connected other switch lead to ground (amazingly difficult to find a good ground - ended up loosening a fender bolt, putting the wire under it and and tightening it back down). Bulb lights. Push pedal, bulb goes out; release pedal, bulb lights. Repeated a few times. What this does is put a couple of amps through contacts that normally only handle a few milliamps (the contacts are rated for three amps, so no strain). The relatively high current burns the oxide off the contacts and restores them to good working order. Biggest problem is connecting to the thin male pins on the switch connector. Since the cabin air temp sensor uses the same connector type, I cut it out and used the female part to connect to the BL switch. Re-installed the cabin air sensor connector with quick disconnects - next time it will be easy! Sorry for the long post - hard to explain in a few words.
 
The following users liked this post:
test point (11-14-2015)
  #20  
Old 06-08-2019, 10:46 AM
Dr. D's Avatar
Senior Member
Join Date: Oct 2010
Location: Near Charlotte, NC
Posts: 478
Received 131 Likes on 100 Posts
Default

Originally Posted by fmertz View Post
FWIW, I went in the other direction. I removed the switch from the car, and took a hard look. There was no obvious sign of bad solder on the pigtail, or anything wrong with the switches themselves. The issue was that the plastic cam that was activated by the brake pedal was worn unevenly and caused the switches to click separately. My understanding is that these switches are supposed to be opposite of one another (one closed, the other one open) at all times, and are built to that effect (one is NO, the other one is NC). When the cam causes one switch to click early in the travel, both switches are in effect at the same state, the computer detects it and throws the error. For now, I ended up propping up the "low" side of the cam with a thin strip of electrical tape, all the while making sure the switches were clicking together. It has been over a week since the repair and the issue has not come back (daily driver), so I am pretty confident in the diagnostic. As to the repair, I am pretty sure the issue will come back once the tape slips, wears out or otherwise stops serving its function. For a more permanent repair, maybe a few layers of glue would do, or alternatively, maybe shaving the "high" side would be easier. Best of luck, keep us posted.
Fmertz:
I am currently at the same place and mindset as you when you made this post in 2015. My question is: Are you still pretty confident in your diagnosis?
I slightly twisted the microswitch lever which in effect did the same as adding tape. I used a stethoscope to hear each switch click. I just did this before seeing your post and I have not yet proven it over time.
Many thanks
 

Thread Tools
Search this Thread
Quick Reply: Brake Light Switch


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: