Relay clicking with van movement

While stationary, if we rock the van by standing on the step, or deliberately rocking it from side to side, a relay clicks on and off.  The relay is located under the bed, in the far right corner of the compartment.  Can anyone tell me what this relay is for and any suggestions why our van might suddenly start doing this?
Four wires go to this relay, purple, purple, slate and white/red.
The relay comes on when the electrics are switched on from the control panel: I hear it click, and if I unplug it then it clicks off
I can't see anything that stops working if I unplug the relay, or while it is clicking
... would really appreciate if anyone has time for a quick answer on this - we are off on a trip tomorrow morning and naturally a bit concerned.
Thanks!

Does your van have self-levelling air suspension?
If I 'rock' my Range-Rover, it too 'clicks' as the sensors on each corner sense the chassis movement & try to compensate, also, if left parked on uneven ground it levels itself after a short while, totally stupid actually!!
Or, could it be some sort of 'anti-rock' sensor to do with the alarm??

No, no self levelling, and no alarm.  From the way and where it is wired, it looks like an Autosleeper addition rather than something Peugeot.  I guess I will call AS in the morning while en-route.  Let's hope it is nothing serious.

Well, since you feel its an A/S fitment, it should be shown in the wiring diagrams page in the handbook, I have a page in my handbook that shows all the relays & their locations.

Regards

Not that one as far as I could find.  There are a couple of possibles on the circuit diagram but not with the right colour wires.  Doesn't seem to be doing it this morning so we are in less of a panic... but will contact AS later.  I'll post the reply for anyone in the future.

Maybe it's yer joints  

Hi Sleepy

Not sure if this is any help to you, but we recently had a problem with our relay 'clicking' on our 55 plate Boxer.

The relay suddenly started 'clicking' whilst travelling.  I discovered that the alternator light was also flashing on and off with the clicking (which was coming from under the driver's seat).  We discovered that the bracket/shield surrounding the alternator in the engine compartment had broken and was shorting out the alternator charging lead.  The relay in our case controls the charging of the leisure battery which is located under the drivers seat.

It is our understanding that the alternator charges the vehicle battery and once this is fully charged, it charges the leisure battery.

The 'culprit' bracket was only held on by one bolt, despite there being 2/3 holes but there is nothing else to bolt it to in the engine.  Our garage has now welded an extension onto the culprit bracket so it shouldn't happen again!  The bracket had also damaged the intercooler.

As a result of the above happenings, the following morning we had a flat battery, however this was soon sorted with a short tow-off!

It's all an experience! 

Solved    we called AS while we were away in the van and by the speed of answering it sounds as if it might be a regular question.
The relay closes to indicate that the water tank is full.  If the van is rocked then the water can slosh around and make the relay click in and out.  Not sure why we haven't had this every time we have filled the tank, but it's certainly the answer - no clicking at all once a bit of water has been used.