MTH crossing lights stopped blinking.

From their product photo, it looks like ad hoc interconnections up at the signal head and between the LEDs and what appear to be additional components (resistors).  I'd carefully examine that area for a errant loose end of stranded wire or the like. 

A bird's eye close-up photo looking down on this area would be useful for the record.

Front and back are in series. 

How many wires go down the pole to the base electronics?

Is 1=3 before going down the pole, is 2=4 before going down the pole, etc.

Here is my pic.  I don't understand what I'm looking for.

Stan, 1 and 3 go down the pole separately. 2 and 4 join and go down on the third wire. 

I'm stumped.    Based on the photos and descriptions we have something like this:

How can the rear-facing pair alternate correctly if both LEDs of front-facing pair are on?!  I cannot see a short-circuit or wiring anomaly that can explain this behavior. 

No doubt the material cost for repair is measured in pennies.  It's the labor/shipping cost for a professional repair that makes what to do not so obvious. 

@Ron045 posted:

 

... I don't understand what I'm looking for.

I was hoping you'd find by visual inspection - or perhaps poking around with a toothpick - something out-of-place such as two wires, terminals, contacts touching each other.

The next step would be to open up the base.

It would be pretty tight quarters with a tiny circuit board as shown above.  The 3 wires coming down the pole are soldered to this board.  As mentioned earlier, the economics of it all is the conundrum.  A DIY'er would no doubt try to repair the board on principle as the most expensive component on the board is 10 cents.

eBay has both new (about $60) and used flashers in varying conditions...presumably you only need to replace one 1 pole.

Good info... Thanks for sharing.  Guess I'll take it apart and see what I can find.

Ron