My MTH switch in straight position, the green bulb on switcher lights up, but when you switch to curve, no red light but transfers to curve and will not transfer back to straight.
Any ideas as to what the problem might be?
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There are a pair of micro switches under the base that control power to the turnout motor and controller. You will have to remove the base cover to access these switches. When the turnout is in the curved position, one of the micro switches is depressed and is electrically closed so that power will be fed to the motor when the turnout is commanded to the straight position, and vice-versa for the other micro switch. When the micro switch is depressed, you should see continuity (closed circuit) between the two tabs that have wires attached. If not, the micro switch is bad or the arm with the roller on it is not being depressed far enough to activate the micro switch. Be careful not to bend it too far or the micro switch will not open when the turnout is thrown. You can hear an audible click when the micro switch is depressed and released. Also, check to be sure that the brass jumpers/buss bars attached to the rails have not detached from them; if so I drill a 3/32" hole through the buss bar and into the rail, then solder the two together. Another item to check, if the switch machine is removed and installed frequently, is the condition of the pins in the socket in the turnout and the inserts in the plugs in the switch machine. The pins sometimes push into the socket and the inserts in the plug will also push through. The pins can be easily viewed in the socket and the inserts are visible through the top of the plug where the barb secures it in the plug. If you can't see shiney metal, then the insert likely pushed through the socket.
Jon, Great tips. Thanks, Joe
