Entrance step buzzing

[Bob Stone]

Last evening when the entrance door was closed a very loud buzzing started down by the entrance step. I could only stop the buzzing by turning on the ignition key with the door closed which caused the step to slide in. When the door is once again opened with the key off the step moves out and there is no noise until the door is closed at which point the loud buzzing returns. We can only avoid the noise by not completely closing the door and leaving it ajar.
The buzzing suggests to me that it's a mechanical relay. Any and all suggestions are greatly appreciated.

Thanks in advance.
Bob Stone

[Steve Huber Co-Admin]

Bob,
I'm guessing, but you may want to check that the motor is not continuing to run. Most stop when amp draw increases, indicating the steps have stopped moving. The other possibility is that the reed switch that the magnet closes is chattering. There is a write-up in Common Problems (Private Members Only board) on entry step operation and troubleshooting.
Steve