Citroen c5 boot problem

[411514]

Im hoping someone can shed some light as to the cause of a fairly peculiar problem, car in question is a 2003 c5 2.0 hdi saloon.

Returning to the car after leaving it parked overnight and found that the alarm had been going off and when starting engine, central display screen indicated that the boot was open (which it isnt).

No amount of slamming and jiggling can convince that car that the boot is shut, and of course as a result i cannot lock the car, (locks and unlocks in quick succesion with a beep from the alarm.

Whilst this may sound like a faulty bootlock motor im not so sure (note the boot lock motor still appears to operate correctly and allows the boot to open as it should do).The problem is not intermittent and occurred whilst parked. Also strangely the rear wiper does not work and neither does the rear window wash although the front window wash does(only just occurred coinciding with the bootlock problem). I was of the understanding that one motor supplied both streams of water

I have checked all the under dash fuses with no luck, and also checked the wiring from car body to tailgate to no avail, but i am absolutely stumped as to what is causing clearly all three symptoms are linked.

Does anyone in the know have any ideas, any help greatly appreciated as currently i am unable to lock the car which is far from ideal, or even how to lock all doors and boot of the car manually as a stopgap measure

many thanks sam

[DickieG]

I'm entirely sure if this applies to a C5 but many cars have a micro switch attached to the boot lock catch which can become detached as the boot is slammed shut, so whilst the boot is locked if the switch is displaced the car's computer will believe that the boot is still open. Refitting the switch and possibly wrapping a thin cable tie around it may well be all that's required.

[wheeler]

The switch that lets the car know when the tailgate is open on the C5 is an integral part of the boot latch/motor.
If i remember right the rear wash/wipe may not operate if the tailgate is open, maybe someone with a C5 could confirm?
Another thing that could cause your problem is brocken or damaged wiring in the little loom that goes between the body & the tailgate lid, maybe worth a look first.

[dnsey]

Do a BSI reset - I bet that will cure it (the clue is that the wiper and window problems occurred at the same time).
Is the battery in good nick? if the voltage drops too far, even briefly, it can cause these kind of glitches.

[411514]

Wheeler thats good thought regarding an open boot stopping the wiper working, i wonder if anyone with a c5 could confirm this.
I have done a bsi reset and nothing has changed.
I believe the battery is in good working order, iv not ever had any problems starting the engine, voltage indicator on the dash always shows well over half way and condition indicator on the battery is green.
I have replaced the rear boot catch and the symptoms persist unaffected.
Strange thing is though that whilst the car thinks the boot is open all the time even when it is shut, the courtesy lights do not light in the boot even when the boot is open so they obvisouly think the boot is closed.
A bit of further digging is required i think, i may try another boot catch in case the replacement was also broken, cheers all, sam.

[myglaren]

My tailgate is wrecked but I can confirm that the wiper won't operate if the tailgate is open.

[wheeler]

Wheeler thats good thought regarding an open boot stopping the wiper working, i wonder if anyone with a c5 could confirm this.

Some VW's, Audis & no doubt loads of other cars wont operate the front wipers if the bonnet is open either.
Have you checked the wiring loom in the rubber boot where it goes from the body to the tailgate ?

[411514]

I have checked the wiring in the boot shut, allbeit quite quickly, i will give it a more thorough check.
Im starting to wonder if it is bsi related simply because if it was a faulty catch or dodgy wiring you might expect it to be a bit intermittent and sometimes work surely. Also was how it started i.e overnight parked up not touched with absolutely no problem with it beforehand.
Am i right in thinking that a lexia may be of use here. Could a lexia detrmine if the catch is faulty or if the fault lies elsewhere (bsi/wiring),
cheers sam

[wheeler]

Could a lexia detrmine if the catch is faulty or if the fault lies elsewhere (bsi/wiring),
cheers sam

No, I wish diagnostic computers could tell you if components were faulty, Lexia could however assist you in finding the problem.
Lexia can let you know if the BSI is seeing the switch beeing pressed or not & it can operate the boot latch but if either the things dont appear to be working it doesent mean the component is definitely faulty, could still be a broken wire.

[411514]

I will draw this to a close for now at least.
Turned out to be just another french phantom fault. Have just been down to the car and thought i would have anther fiddle to see if i could sort matters, anyway completely works, no problem at all even with the original boot catch.
Whilst im a bit annoyed that i now have three boot catches and wasted a whole day trying to fix it i am relieved that i dont have to spend any more time and money messing with it.
Thanks to all those who replied particularly wheeler some good thoughts there, so if anyone needs a replacement boot catch they know where to come, cheers sam