We have 4 low voltage light fixtures on our walkway. They're Nightscaping GD-1606 Quadliters, about 10 years old, and have been nothing but trouble. Hoods difficult to remove, bulbs difficult to replace.

Recently one of the fixtures stopped working, for no apparent reason. The bayonet bulb is good, and is the proper voltage. I cleaned the bulb contacts and fixture contacts with emory cloth. I used a multitester to see if there is voltage to the contacts, and there is about 12V, just like there is to the other 3 fixtures, yet the bulb still will not illuminate. Any ideas?

I can't imagine there's anything wrong with the transformer, or more fixtures would be affected. Also, no one has done any digging near the underground wires, so I don't think they got nicked. Makes no sense that the fixture is getting 12 volts, according to my tester, yet the bulb will not light.

Thanks.