neons went out :( help plz

One of the first things to check when there is a problem with a 12 volt DC product is your grounds. Since they were working and just quit, there could be a problem with the transformer. Make sure you have the wiring grounded to an area that has been cleaned thoroughly, and the paint has been sanded off.

Alan

Sounds more and more like the transformer could be defective. When they go out: are they just snapping right off or do they flicker/dim before going out?

Something tells me the install is ok, but there may be a bad part involved. See if there is any unusual warmth when you touch the transformer, i'm thinking the source of the problem is there.

Alan

It could be a transformer problem. Just for fun, check your connections leading to the transformer. If you used some type of crimp-on connectors, give them a firm tug to see if the connections are tight. A loose fitting could give you the intermittent operation you are seeing.

My suspicion still rests in the transformer... Can you get a replacement easily?

"Edit": Ok, I went and read the installation instructions for the kit you have. It said you are not to use crimp-on connectors, so I assume you didn't. The reasons for intermittent operations seem to be:

transformer is grounded improperly, painted not sanded to bare metal at grounding point.

Neon tube may be cracked, this causes entire kit to act weird.

Poor connections made between transformer and tubes, check them like I stated above.

Alan