Garden light system is tripping the circuit breaker

Hello all, people seem quite helpful on these forums so I've signed up specifically to ask this question.

We have an electrical system in the back garden that powers 5 or six garden lights, a pump (disconnected) and a garden house. This is all connected to a switch in the living room, which opens onto the garden. 

Recently, when the system is turned on, and either the lights or the garden house lighting is turned on, something is tripping the circuit breaker and everything in the garden goes off including part of the living room and some other sockets.

Here is a picture of one of the lights (it's old and there is moisture inside the cover) plus a photo of the inside of the little box attached to the side.

One of the lights and the little box, here you can see the cord going off to the left that gives power to the light fitting.

My first question is, could this old light with moisture in the fitting be causing the circuit to trip? If so, could I remove it entirely without too much hassle?

I also found this setup, which was powering a light and a pump, which is now disconnected. There was also a cord that used to go to the pump just loose like this, could that be causing trouble?

Basically I want to know if it's something simple, like one of the lights is making the circuit unstable, then I can look at that first. If, however, those little boxes are designed specifically so that doesn't happen, then I guess I have to look at the cables between these boxes (and the boxes themselves).

Thanks, and sorry I couldn't make this question any more concise

Jason

probably easier to rip it all out and start again

Andy™ said:

probably easier to rip it all out and start again

Click to expand...

That is definitely an option in the long term, but I should mention that in the short term, I'd just like to get it stable so we can use the power in the garden house in the meantime.

That cable could definitely be an issue, as could that damp light. Cabling is probably fine, just a poor choice of boxes and lack of maintenance on the lights.

Really needs testing to be sure.

Thanks for the info. So from looking at the inside of the box, I should be able to disconnect the wires going to the light fitting and remove the bad ones from the whole equation, no?I'm not going to get much more involved than that before calling a professional, but I'd like to rule them out before spending money.

Don't forget to close the nylon glands right up if you remove the cable to the lights.

Aziraphael said:

So from looking at the inside of the box, I should be able to disconnect the wires going to the light fitting and remove the bad ones from the whole equation

Click to expand...

Would appear to be the case.