Boot Won't Open On A 2011 C5 Tourer - Wiring Damaged Near Hinge

[cookiemonster]

Mine is a 2011 Citroen C5 Exclusive tourer with a powered boot/tailgate.

 

The boot will not open. When I press the boot release button on the keyfob or the button on the outside of the boot itself I hear two beeps from inside the boot and the boot does nothing. It will not open manually either (i.e. it is locked shut).

 

Once the boot is released from the inside (using the emergency release procedure) it will raise or lower itself on pressing the keyfob, the button on the outside and the red button on the inside, so I know all buttons are working and so is the powered lifting/closing motor.

 

I deduce from this that the lock itself is faulty: either it is not receiving a signal to open or it is not acting on that signal. Could it be the problem covered at http://www.citroen-owners-club.co.uk/citroen/topic/22861-boot-lock/ (though this I think was the previous 2009 model)?

 

Any views please? I am thinking next step is to fit a new lock/latch.

[paul.h]

That topic is for the current C5 so I would work your way through the things suggested and not buy any parts yet.

[cookiemonster]

Thank you for your response Paul.

 

Sorry not sure why I thought 2009 was the previous model.

 

I will work through the steps in that post this weekend when I have some daylight.

 

However, given that I hear two beeps from inside the boot when I press either the boot release button on the key fob or the button on the outside of the boot itself, this says to me that both buttons are successfully sending a signal to the bsi. So I suspect the fault is either with the wiring from the bsi to the lock, or with the lock itself. Presumably I could test this by removing the lock and doing some kind of continuity test on it? Not really sure how to do that.

[paul.h]

You could test the lock with the boot open by closing the lock against a screwdriver and then seeing if it unlocks with the boot switch or keyfob.

[cookiemonster]

I took the lock out tonight, closed it and forced 12V through it direct from the battery. It opened. So it appears like the lock itself is not to blame. I think that leaves just one culprit: there must be something preventing current getting from the bsi to the lock. Given the two beeps I hear from something very close to the lock when I press any of the buttons, I suspect the problem may lie in the final few inches? I tried to put a voltmeter on the plug which goes in to the lock and pressed the button on the keyfob. The voltmeter did not register any current but then it is very difficult to get the probes in.

[paul.h]

Most likely place for wiring damage is in the bit between the door and body.

[cookiemonster]

As you thought Paul it was a broken wire near the boot hinge. 

 

Fixed that and now on to the next electrical gremlin - tyre pressure monitor telling me the LH rear tyre is punctured when it is not.

[paul.h]

If the tyre pressure is correct, then it could be the pressure sensor needs replacing. On some cars they do not have sensors but instead use the abs ones to check the wheel rotation.

 

I have edited the topic title slightly.

[cookiemonster]

Thanks Paul. I think these sensors are the active/direct type, not the ones that use the ABS. £120 each sadly, and nowadays an MOT fail if they are playing up. Sometimes the technology is less of a help than a hindrance!