After extended use we have seen a few cases where the potentiometer fitted to our RBT series of hand control boxs have rotated slightly in their mounting brackets. The symptom is that the motor will not stop completely, or change into reverse [depends on controller model and settings]. The photo below shows the green body of the pot in its correct position, rotated fully anti-clockwise with the solder tags slightly below the horizontal.
If yours is different to this, press gently down on the point indicated above to rotate the pot in its mounting, and then tighten the pot nut with a 14mm spanner.
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