Dogging on the Wirral

Hi All, I'ma a dogging newbie, I have never done it!! I went to a few locations renowned for being dogging hot spots, and waited in the car. So far 2 cars have been & gone. The first pulled up, the couple had the light on, then turned it off, they had a mobile phone light on a couple of times, but I don't know if that was a sign? The second pulled up behind then turned their light on inside the car, then turned it off, a while later they put it back on for a few seconds then off again, a while after that I heard a very short bip of the horn, not sure if they accidentally knocked it....

After about 20 minutes in both cases the cars drove off.

I'm very cautious about approaching the car, & I need to know when to do it. Should I have gotten out of my car in the above examples & gone over to the other car to see what what happening inside, even though it was dark? Where they inviting me?? I don't want to go over to the car from mine in the dark & frighten the living daylights out of somebody & cause a scene for the obvious reasons...

Any advice most appreciated??

Thank you

Chris