Hello everyone and happy New Year!

I had a problem with a some site lighting at a residence a couple days ago where the owner said he could not get half of his walkway lights to work. It is a 12 volt system and when I check them out 3 of them are working but the other 7 are not. I figure there is a bad splice so I re-splice a 3-way connection after the 3 light (the farthest one from the x-former that worked) and when I turn them on I get 12 v at the connection for the next light but when I hook that light up the votage drops down to zero at that connection but the first three lights are still working. There were ten 25watt fixtures on a 250 watt x-former so I am assuming that I need to replace the x-former but I don't see an explaination on the voltage differences on the same system. Anyone out there have any input on this.

Thank you
John