Issues with MTH Crossing gates and relays

Are the gates "permanently" stuck in the down position with lights flashing even after train leaves the insulated section of rail?

Jim S posted:

Hi guys.  Trying to get my MTH 30-11012 crossing gates to work.  Wired them to my DPDT relay (the relay is from Scott's Odds n Ends) as per the wiring diagram.  The gates go down, the lights flash when the train goes over the insulated section of rail, but the gates do not go back up.  The gates worked just fine on my last layout but I am stumped as to what I did wrong here.  Any and all ideas are welcome.  Thanks 

what happens if you run the trains in the opposite direction?

Stan, yes the gates a stuck in the down position.

Ok, to help on this, stan2004 helped me with crossing lights and relays a year back and one thing I've had an issue with and still happens, is the same thing you have here. But it only happens not all the time unless I leave it. What happens, between the rails where the insulated part is at each end of track where the pins are, with the ballast in the track as the train passes over, the ballast vibrates and makes a contact between both rails and after that I have to brush away a tiny speck of ballast away from the rail insulator connection pin area by the track end pins and then the gates will rise. Now this could be different with your layout, but with mine this has happened sometimes, but not very much. But I thought I would let you know in case this might be part of the problem.

Good call, Tom. It sounds like the rail isn't isolated. I have the same problem where I haven't quite cut the track through or where I pulled the pin on Fastrack and it is to close to the regular track.

The lights flash when they are supposed to and go off when the train is off of the insulated track section.  I will play with it some more later.

I believe the Scotts relay is no longer available so did not readily find a wiring diagram, but I figure the wiring is similar if not identical to this "courtesy" of Azatrax and their MRAPR Relay.

Here's what I suggest you do.  Swap the yellow and white wires where they connect to the Scotts relay module.  These 2 contact/connections terminals will likely be labeled NO and NC.   This should just make the gates operate backwards (gates down and lights flashing when no train present, gates up and not-flashing when train present).  I figure this should only take a minute to try.  But this will isolate the problem.

I realize your train room may be a noisy venue, but perhaps it's possible to listen or even put your finger on the gate mechanism when the gates should go up.  I'm wondering if you can hear/feel the mechanism thump, jerk, click, or whatever and is simply mechanically stuck in the down position.  That is, power could be applied but something is jammed preventing it from rising.

Addendum:  I found the thread I was thinking about here.  Apparently a plastic gear can break so the motor spins but there's no transmission to effect gate arm motion.  I'd think you can hear/feel the motor trying. 

If the mechanism is silent when it should be going up, I'd be thinking about an electrical issue - loose, broken, shorted wire which might be found by visual inspection.  An electronic component failure would obviously be a trickier repair.  Here's another thread showing the electrical guts which may help you decide if you want to pursue this route.

Thanks, Stan,  the diagram you showed is the one I'm working with.  I'll try swapping the yellow and white wires and we'll see what happens.  

If accessible, try them one at a time. It seems odd that both do not go back up With power to the red and black, touch the yellow to the blue, or white to the blue, and they should react.

Still stumped.  Swapped the yellow and white wires, touched the yellow to the blue, the white to the blue and still the gate doesn’t react.  The lights flash when I run the boxcar over the insulated rail.  Odd.

As John says it's odd that both gates are stuck in the down position. 

I think the next step is to pull the gates from the layout and try them one-at-a-time connected to a power supply.  Red & Black to the power.  Yellow to Blue (White open) should make gates go down (albeit already down) and flash lights.  White to Blue (Yellow open) should make gates go up and lights stop.

What changed "electrically" between your current and previous layout where they apparently worked?  And did it work just one time on the current layout?  That is, the gates went down and have been down ever since.