Hi all,
does anyone know the location of the central locking control unit in a 2001 xsara estate?
central locking control unit
Moderator: RichardW
Is that what would be referred to as the 'body computer'?
I have a fault with the central locking.
It started about a month ago. The radio would beep every few minutes and tell me the left front door was open when it wasn't. If I locked the doors the warning would stop. Eventually the warning returned even when the doors were locked, it would unlock itself. I then had a problem locking the doors. I would press the lock button on the keyfob, it would lock then unlock. After several attempts it would eventually lock. Not anymore though. I've had to remove the fuse so back to manual locking. I can't open the boot anymore though. Sometimes when I open the front passenger door the central locking will lock/unlock itself.
I've read on other forums there is a known issue with the xsara/306 wiring looms in the doors. I've inspected the loom on both the driver and passenger sides and can't see any visible breaks.
I was hoping to use a work around but the info was for a 306 and the xsara seems different where electrics are concerned.
I'm now resorting to getting the multimeter out and inspecting the looms for internal breaks.
Given the above information would you start with the driver or passenger door?
I have a fault with the central locking.
It started about a month ago. The radio would beep every few minutes and tell me the left front door was open when it wasn't. If I locked the doors the warning would stop. Eventually the warning returned even when the doors were locked, it would unlock itself. I then had a problem locking the doors. I would press the lock button on the keyfob, it would lock then unlock. After several attempts it would eventually lock. Not anymore though. I've had to remove the fuse so back to manual locking. I can't open the boot anymore though. Sometimes when I open the front passenger door the central locking will lock/unlock itself.
I've read on other forums there is a known issue with the xsara/306 wiring looms in the doors. I've inspected the loom on both the driver and passenger sides and can't see any visible breaks.
I was hoping to use a work around but the info was for a 306 and the xsara seems different where electrics are concerned.
I'm now resorting to getting the multimeter out and inspecting the looms for internal breaks.
Given the above information would you start with the driver or passenger door?
I think the term "body computer" refers to the earlier setup used before multiplexing was introduced (eg on a Xantia, mk1 Xsara, 306 etc). When the mk2 Xsara & the Picasso were launched the wiring setup changed radically from what had gone before, so you will probably find the specific details on 306 wiring don't have much in common with a mk2 Xsara.
The BSI's job is apparently a central control unit for the various other ECUs in the car, and also stores anti-theft codes for the immobiliser and locking remotes.
Although the electronics are very complex, most of the problems with Xsara central locking appear to be caused by fairly mundane things like dodgy wiring loom connections to the doors, or sticking/worn door lock mechanisms, which seem to be a common fault.
My Xsara went through a phase last winter when it would sometimes lock/unlock the central locking just as the drivers door was opened. I cleaned up the plugin connectors to the front doors, and the problem stopped, but I'm not sure whether my intervention had anything to do with it, or just the warmer weather. It was always very cold weather when it happened for some reason.
The BSI's job is apparently a central control unit for the various other ECUs in the car, and also stores anti-theft codes for the immobiliser and locking remotes.
Although the electronics are very complex, most of the problems with Xsara central locking appear to be caused by fairly mundane things like dodgy wiring loom connections to the doors, or sticking/worn door lock mechanisms, which seem to be a common fault.
My Xsara went through a phase last winter when it would sometimes lock/unlock the central locking just as the drivers door was opened. I cleaned up the plugin connectors to the front doors, and the problem stopped, but I'm not sure whether my intervention had anything to do with it, or just the warmer weather. It was always very cold weather when it happened for some reason.
Instead of traditional circuits, multiplex wiring is a sort of "ring main" setup, where a central computer sends signals down a shared cable, telling each piece of equipment on the car when to switch on or off.
All I did to the connectors was to unplug them, spray in some WD40 to get rid of any damp, then plug & unplug them a few times. I'm not convinced this made the difference though, I think low temperature & perhaps moisture were to blame, maybe causing the drivers door lock mechanism to stick. I probably won't know for sure until next winter!
All I did to the connectors was to unplug them, spray in some WD40 to get rid of any damp, then plug & unplug them a few times. I'm not convinced this made the difference though, I think low temperature & perhaps moisture were to blame, maybe causing the drivers door lock mechanism to stick. I probably won't know for sure until next winter!
Oh dear, that doesn't bode well for my 'fix on the cheap' idea does it?
Come to think of it, the problem did start during an especially wet period of weather. The liberal use of WD40 on the door plugs has already been tried...
One thing I haven't yet tried is WD40 direct into the lock. Do you reckon it could make a difference?
Come to think of it, the problem did start during an especially wet period of weather. The liberal use of WD40 on the door plugs has already been tried...
One thing I haven't yet tried is WD40 direct into the lock. Do you reckon it could make a difference?
Thanks for the help so far.
Right, I've replaced both the driver and passenger side wiring looms and there is no change.
Something eelse I have noticed is the 'door open' light on the instrument panel will not immediately light up when the front passenger door is opened. If I keep pulling the interior or exterior door handle the light will switch on.
Any ideas?
Right, I've replaced both the driver and passenger side wiring looms and there is no change.
Something eelse I have noticed is the 'door open' light on the instrument panel will not immediately light up when the front passenger door is opened. If I keep pulling the interior or exterior door handle the light will switch on.
Any ideas?
Sounds to me very much like a dodgy lock mechanism on the passenger side then. You've eliminated the other most likely cause, the wiring to the doors, so I think its got to be the mechanism itself.
Its the lock that passes info back to the BSI on whether the doors are properly closed or not. I'm not sure how exactly it does this, my guess would be through a microswitch inside the lock. If they aren't properly closed (or it thinks they aren't) the system will either refuse to lock at all, or will let you lock it but it will unlock itself again afterwards. It can also make the "Door Open" warning, and the courtesy lights behave oddly too. There aren't the usual push switches on these to operate the interior light, its all done by the lock mechanism.
I don't know whether its possible to do any dismantling of the lock or if replacement is the only answer. A visit to a scrapyard might be worthwhile, I don't think they're all that expensive from a dealer though.
From the symptoms you describe it sounds as if the drivers side lock of my car is also in the early stages of the same fault, perhaps with mine the cold/damp was just enough to make it stick slightly.
Its the lock that passes info back to the BSI on whether the doors are properly closed or not. I'm not sure how exactly it does this, my guess would be through a microswitch inside the lock. If they aren't properly closed (or it thinks they aren't) the system will either refuse to lock at all, or will let you lock it but it will unlock itself again afterwards. It can also make the "Door Open" warning, and the courtesy lights behave oddly too. There aren't the usual push switches on these to operate the interior light, its all done by the lock mechanism.
I don't know whether its possible to do any dismantling of the lock or if replacement is the only answer. A visit to a scrapyard might be worthwhile, I don't think they're all that expensive from a dealer though.
From the symptoms you describe it sounds as if the drivers side lock of my car is also in the early stages of the same fault, perhaps with mine the cold/damp was just enough to make it stick slightly.
Thanks again for the advice nick.
Is the part I'm looking for called a lock mechanism then?
I've got a Haynes manual but it only covers to model year 2000. Would it be the same process to replace the mechanism? If so I reckon I could manage that.
Your explanation of the micro switches make perfect sense, I think one of them can't decide whether it's closed or not.
About the cold/damp thing. It rained quite heavily on sunday and it caused the 'front left door open' warning to appear while driving again. It's stopped now with the hot weather.
Is the part I'm looking for called a lock mechanism then?
I've got a Haynes manual but it only covers to model year 2000. Would it be the same process to replace the mechanism? If so I reckon I could manage that.
Your explanation of the micro switches make perfect sense, I think one of them can't decide whether it's closed or not.
About the cold/damp thing. It rained quite heavily on sunday and it caused the 'front left door open' warning to appear while driving again. It's stopped now with the hot weather.
No problem. I don't know if "lock mechanism" is the official name for it, thats just what I call it!
It shouldn't be too difficult to change and I guess that aspect of it will be virtually identical to the old shape Xsara. I haven't had the pleasure of doing this job yet on a Xsara, but I did on my old Xantia not long before I sold it. Basically remove the interior door trim, disconnect the operating rods & electrical connector from the mechanism, undo any bolts holding it to the edge of the door, then slide it out.
By the way, I emailed Haynes last week to ask if they had any plans to update their Xsara manual to cover the later models. "No" was the answer
It shouldn't be too difficult to change and I guess that aspect of it will be virtually identical to the old shape Xsara. I haven't had the pleasure of doing this job yet on a Xsara, but I did on my old Xantia not long before I sold it. Basically remove the interior door trim, disconnect the operating rods & electrical connector from the mechanism, undo any bolts holding it to the edge of the door, then slide it out.
By the way, I emailed Haynes last week to ask if they had any plans to update their Xsara manual to cover the later models. "No" was the answer
A big thank you to you nick!
I bought a used lock mechanism off ebay for £24 delivered.
Only just fitted it, took a good couple of hours and....
It's working!
I was getting sick of pulling the cl fuse to manually lock it, then having to put the fuse back in to access the boot.
My wife has just given birth to our second daughter so frequent boot access is really important.
Thanks again!
Ian.
I bought a used lock mechanism off ebay for £24 delivered.
Only just fitted it, took a good couple of hours and....
It's working!
I was getting sick of pulling the cl fuse to manually lock it, then having to put the fuse back in to access the boot.
My wife has just given birth to our second daughter so frequent boot access is really important.
Thanks again!
Ian.
