Automatic running boards

[James Macklem]

2018 suburban.... Passenger side running board will go halfway up then back down and stay down. Every time. Driver side works fine, I can see no obstruction, and I removed the board in case it was out of alignment. Still went halfway up and then down to stay. Any ideas? 

[Russ Swift]

1.  Check power source to running board.

2.  Check function of drive motor, or what ever it is, that moves the board.

3.  Find something different between working and non working board

4.  Check for an electrical resistor or some other in line electric item.  
5.  Check fuzes?
Can’t think of anything else, but it has to be something that is working on one side and not on the other, or something that controls both sides and is not working correctly.

Just my 2 cents.  Good Luck.