[Baz]

Photos are always helpful.

Also, there is a way to troubleshoot where certain components can be eliminated as the problem.

Start with transformer - measure output in volts. 12v? Good.

Hook up cable and connect to known good light fixture. Comes on OK? Good.

Now you know the transformer and cable are OK.

One by one re-connect each fixture.


Other than that - the problem might be associate with a deterioration of your components and/or connections due to weather and natural elements.

Like I said earlier - it's very basic and should be straight forward to toubleshoot...