What's that clicking??

[Newbi]

Hi all
While in the garage last night I heard a relay like clicking sound coming from my sl500 every 10 seconds or so. The alarm in not armed, so just wondered if anyone knew what this might be.
I am wondering if it has something to do with the fact that my electrical consumers offline shows up most times I start the car, even after just a day of not being used.
It doesn't seem to cause any problems but I'm just curious as to what it is.
Cheers

 

[Dieselman]

Is your car suspended on air, if so, I suspect the air pump relay to be operating.

 

[shirleydrive]

Almost certainly the purge control valve. Don't worry about the clicking. This is normal operation.

Mike

 

[Dieselman]

Almost certainly the purge control valve. Don't worry about the clicking. This is normal operation.

With the car switched off?

 

[Newbi]

Cheers guys
The car is switched off when happening.