Sorry for bothering, but I guess I need someone pointing me into the right direction...

After our X100 XKR Convertible had an accident, the Drivers Door had to be replaced.
I purchased a used one from a scrapyard and today I got the car back from the paintshop.

Problem: the interior light does not switch off. Even when driving.
Also the Remote Control does not operate the central locking anymore.
When I lock the door with the key, you can still see the window moving when I pull the doors handle.
When I operate the the pushbuttons of the reading lights, you can see them getting a bit brighter and darker... so the buttons seem okay.

Everything was swapped from the old door to the new one.

Any Ideas what could cause this behaviour?

BR
Ralf

 

My car was experiencing some of these symptoms whenever I bought it.

In my case I had a damaged door wiring harness. More specifically, it was water damaged.

I also had some burnt traces in my door module that I had to repair, but that was stopping the window from operating at all. It sounds like your window is operable, even if a little non compliant.

 

Thanks a lot for that, but I'm totally confused at the moment.

Why?
Because the Window operates perfectly!
Because the Window is lowered, when i pull the handle, and moves up when I close the door.

So the door closed switch seems working ...

What can the central locking and remote control prevent from functioning?

Luckily the indoor lights are turned off after some time.

 

I had the same questions and disbelief whenever i was originally working on it. I did eventually figure out the reasons why though.

The functions of the car are going to be performed locally and remotely by modules.

The local door module in your driver door is connected to sensors and loads.


The driver door window switch, mirror switches, sensor that detects when the key has locked the door, sensor that detects when the door handle has been opened, and sensor that detects when the door has been closed.
Not an exhaustive list, but we can talk about these really quick. These are all sensors, although some are actually the same sensor lets ignore that, that are local to the driver door control module. The computer in your door has direct access to these. So the driver door module knows that the door is open or closed. It can check the status of that sensor.

The window is a driven load from your driver door module. It also has direct communication with your door module and will work happily.


The locking and security module is located in the trunk however. It does not have direct access to the sensors in your drivers door to know whether the door is closed, or the window is up, or if you have pressed the lock button on the drivers door.
It uses the CAN bus to communicate the status of the sensors and loads to the other modules in the car.
Right now your can bus for your driver door module is not working properly, whether it is the cables in the harness, or the door module is not properly sending data on the CAN bus, that is for you to discover.

Your BPM that controls the lights, and your Security and locking module can't get the information that they need to operate properly from your drivers door control module. They are asking it whether or not the door is shut, and whether or not the windows are up. The drivers door isn't sending that information out to the rest of the car right now.


So, that is the how.

The why, in my limited experience, was due to a water damaged corroded wiring harness that inhibited communication on the can bus wires. I suspect that you will find that you are experiencing the same.

Is it possible that it is a damaged door control module? Yes it is. It would be less likely in my guess however.


The previous owner of my car dealt with both of the doors of my car not being able to communicate on the can bus for the last 3 years that they owned the car, because the repair shops weren't smart enough to even check the integrity of the wiring harnesses, instead just throwing new door control modules at the problem until the owner eventually gave up with the problem unresolved.


EDIT: For anyone else reading, michaelh pointed out below that it is indeed the SCP bus, not CAN bus that these modules communicate on. Ultimately doesn't change much about what I said, but it is definitely an important distinction.

 

Hi Dougie,
I think Mad Hatter is very much on the right lines here, except it's SCP bus rather than CAN for this inter-module dialogue.

The door module seems to know whether the door is open or not as the window is behaving. However, the rest of the car doesn't appear to as:

1) Interior lights don't go out:- controlled by BPM. If it doesn't know the door is closed, it wont turn the lights off (OK, they do timeout anyway after a while as you note - my car behaves like this if a door is open)

2) Remotes won't lock:- SLM doesn't know if the door(s) are closed, so it won't attempt to lock them (again, that's how my car behaves)

I suspect there's either a wiring harness issue or, possibly, the driver's door module has been damaged. Check the connectors and harness around the door for continuity - SCP bus wire colours are blue and yellow.

Curious:- I guess you're not getting a 'door open' warning in the instrument cluster? The door module sends out both 'I'm closed' and 'I'm open' messages.



P.S. Don't be sorry:- this is why we're all here

 

Oh that is right, i always forget that for some weird reason they used multiple com buses in this car.


@michaelh Mine defaulted to door open warning messages for the driver door when it couldn't communicate. Not sure if that is the same for everyone though.


Also not only should you be checking those wires for continuity but for resistance.

 

Hey MH I've just reviewed the thread and I read like an echo of your post...

Absolutely no criticism intended from me. I know that you're now intimately acquainted with the CAN on our cars

Surely the same thing??

 

Oh, i definitely wasn't upset. I am always glad to be corrected. Don't want to spout incorrect information, which I was.


I may be wrong on the terminology, but I have always understood that a continuity check was just checking that there is a connection. Be it a light or a beep test or an actual resistance reading.
Whereas a resistance check would actually be a measurement of the "quality" of the connection.


He may have a proper physical connection in the SCP bus in the wiring harness that would pass a light or beep check, but if he read the ohms of resistance then it would be too high of resistance for it to communicate properly.

I imagine we are only differing in semantics here.

 

Hey again - what's with the grey ink on the grey background? - or were you whispering

Indeed:- in the context of low-current wiring looms I'd expect the resistance to be no more than an ohm or so.

 

Afraid I don't know what you mean.

Yeah if they are in good condition. But if they are damaged that might not be the case.

 

Odd. I see your previous quote like this:


Damn computers...

 

Ahh. I use a dark skin for websites that use bright colors, so that it doesn't stress my eyes as much. Sometimes text will end up matching the background color as a result. It is a bug in the software i use.

 

You are both great guys and I thank you sooo much for the analysis which makes perfect sense to me!
I feel honored for the effort you took helping me out. I owe you one!

Unfortunately I wasn't around when the guy from the paintshop installed the new door and swapped all the electronics, but I asked him if he had disconnected the battery when re-installing everything. He wasn't sure but tended to "no".

So my only question: would it make sense to disconnect the battery at this point in time to force a kind of reset? Just in case this might be an easier option to try before dismantling the door again :-)

I'm optimistic that this will work again soon, because it has worked before without any problem. Here in Germany we have "Contact 60" fluid, which does a good job to corroded contacts.
Maybe it's a kind of loose contact, because I remember after opening an closing the door a couple of times trying around, there was a single moment, when the car reacted on the remote control.
But without your explanations I wasn't able to put hat behaviour in the right context. So: thanks again! I will report further!

BR
Ralf

 

I always default to removing negative battery cable before I would do any electrical work. I think it would be a good idea to at least try this.

Anytime the battery cable is disconnected the window positions will need to be relearned and the emissions drive cycles will need to be completed again.

Some people have had success with cleaning the contacts in the door jamb connector. Definitely wouldn't hurt to try it. If that is the problem then it would save you the trouble of taking the door panel off.

Good luck to you.

 

From what you say I understand the the door jamb connector is the one visible when the door is open?

Would be indeed the easier option.... however: at some time in the future I have to take off the panely anyway, because from the previous owner there's a clip missing which holds the panel tight to the door. But this is not electrical :-)

 

Yessir. It is a round connector with ribs on the outside that will destroy the skin on your thumb if you let it.

I had to use a strapwrench around it to get it loose the first time.

It is threaded, although in somewhat of an odd way. You will see when you go to remove it.

Just pull out on the connector when you are trying to spin it and it will free it up much easier than if you are rotating alone.


When you get around to taking the door panel off, make sure you have lots of extra panel retaining clips. And also make sure you have lots of epoxy that you can sculpt with. The panel retaining clips are held to the back of the door panel with plastic stands that are glued to the panel. Those plastic stands break, come unglued, and the plastic retaining clips break as well. It is fun, you get to be a sculptor for an entire afternoon.

 

Gentlemen?!

That was GREAT STUFF!
Just came home and disconnected the door jamb connector and flooded both sides with Contact 60, reconnected the connector, programmed the window positions and tadaaa: everything is working again!!!

I have to thank you and the whole forum again for such a fantastic assistance!

So the last fault I have to identify will be the amplifier in the trunk from the Jaguar Premium Sound System, which does not switch off.
I already sent an email to Alpine in UK asking for the service manuals, but did not get a response so far. But that's a different issue.

BR
Ralf