Hi everyone
Last year I had the hydraulic pipes replaced for the convertible roof which suffered from the common 'green shower' leaking pipe across the top of the windscreen! every since the hydraulic pipe replacement the message centre comes up with 'check rear lights' every time I use the car - it seems the message comes on even when I am not braking, indicating or using any rear light at all. I have checked all bulbs, indeed I have replaced all of them just to be sure but the message still appears. I am thinking there is probably a weak cable connection somewhere or a sensor. has anyone come across this before and can offer advice on the potential cause?

Many thanks in advance
Graham

 

Did you check the rear License plate lights ? Unsure if these are connected to the Jaguar warning system - but they certainly are on Ford cars.....

 

Sounds like Brake micro switch. Thread located here somewhere explains it all in detail.

 

I did check the licence plate lights and also replaced them just in case but still no joy!

 

Thanks Sam - will check that out
Cheers

 

2 possibilities - brake micro switch or burnt ground lead on the connection going to the rear lights. Disconnect the harness going to the rear light assembly and look at the black ground lead - is it charred/damaged? If so follow the link below to install a separate ground lead and all will be good (saved me $1700 when dealer was telling me BPM needed replaced)

https://www.jaguarforums.com/forum/x...d-35083/page2/

https://www.jaguarforums.com/forum/x...removal-84826/

 

Great thanks - I will certainly check this one out!

 

This is driving me nuts! checked for a burnt out earth lead and everything in remarkably good order - looks like the brake switch is next to try
what I don't understand is the warning 'check rear lights' always comes up after driving about 5 minutes or so and every time I am just driving in daylight not indicating or pressing the brake pedal, it just doesn't make sense at all

I will keep investigating and try to get to the bottom of it

Thanks everyone for your suggestions so far, very helpful

 

Like everything 'Jaguar', the brake switch controls more than 1 thing. Try replacing, or rebuilding the micro contacts. There is a thread here about it.

 

To my knowledge, the rear lights are working under some form of monitoring by the control module, like an alarm system. Basically, the control module has a low current running through the circuit at all times so when the circuit is open, it can warn you of a failed bulb. In this design, bulbs are assumed to be resistive (old filament type). The older LED bulbs sometimes give the same message, but there seem to be newer "CAN" bulbs that claim to work.

From memory, a failed sometimes-open circuit gives the check-rear-lights message alone. When the brake switch fails, it gives another additional message about cruise control.

Best is to check the electrical guide and figure out what other bulbs/sockets are on that monitored circuit.

Best of luck, keep us posted.

 

I would first check your rear lights and make sure the bulbs are working. Press the brakes and make sure those lights are working as well. On my car I had a brake light bulb that would work intermittently and would pop “check rear lights message” every now and then until I finally replaced the bulb.

Another issue I ran into was my brake micro switch went bad. Instead of buying a new assembly I elected to buy a solder gun and new micro switches the part number I used was D2HW-A211D-ND from digikey cost being about $13 + $15 for solder gun. No messages since.

 

You will save significant money and have a much better brake pedal switch assembly if you opt to replace the two microswitches with more robust ones rather than purchasing a new OEM switch assembly. I learned that fact after going through two OEM replacements back when the car was my wife's daily driver from early February 2012 until late October 2018....

 

fmertz is correct. If the microswitch is bad, you will not have cruise control, and get that msg. also. Without a problem with the Cr. Cntrl, you likely have a bulb out, or one has been replaced with an LED.

 

Thanks for all of your advice - still a mystery! I have replaced all rear light bulbs, Cruise Control works perfectly, I even put the additional earth cable on even though there appeared to be no problem with the original cable or connection, still the check rear lights alert comes on
I think I will now change the brake switch even though it is showing no signs of fault to see if that cures the problem
Jon89 - thanks for your advice regarding a more robust switch which I will opt for. Could you please tell me where I can obtain or indeed what I am asking for as apposed to OEM?
Thanks again everyone - will keep you all updated when I finally sort this annoying problem

 

High-quality microswitches can be obtained here in the U.S. from www.mouser.com. Not sure about sources in the UK. As previously mentioned, when these OEM brake switch assemblies begin to fail, the alternating flashing message on the dashboard display typically reads "CRUISE NOT AVAILABLE" and "CHECK REAR LIGHTS". You may have a different issue....

When you replaced your rear bulbs, did you clean and burnish all of the sockets first? If not, I would do that next. I would also have a good look at the bulb wiring harnesses for any sign of corrosion or damage....

 

Thanks Jon very helpful
yes indeed I fully cleaned all of the electrical terminals and everything looks good for an electrical connection. I have no idea if this problem is a coincidence or not but it started to happen directly after I had the full front to rear hydraulic pipe replaced for the roof as I suffered from the dreaded green shower! therefore I am wondering if maybe a connection in the wiring loom may have been dislodged - I think I will try to obtain a wiring diagram for me to then see which part of the loom is relevant - does anyone know if wiring diagrams are available?

 

Very possible that your green shower repair effort may have caused your rear lights issue since a lot of that work is done in the trunk where it is easy to accidentally bump things around....

You may find the wiring diagram you need on the website that long-time forum member Gus runs. Go to JagRepair.com - Jaguar Repair Information Resource and do some searching....

 

Fantastic thanks Jon, I will check that out
Cheers

 

Jon - thank you so much for pointing me to Gus's site - I will be in my element reading through everything there - what a fantastic resource!

 

Gus is indeed one of the gurus here on the forum. Always willing to help and a true fountain of Jaguar knowledge....