General troubleshooting steps are:

• Run wheels forward and backward for at least 60 s in each direction

If needed, open the waterproof box (4 screws) and check the following:

• Measure voltages on the 3 pole connector in the green box (both directions)
• Measure voltage over motor poles in green box (both directions)
• Release spreader with black button on the side of the green box, center it and run wheels again

If hose spreader does not run equally far in both directions, use a wrench to rotate the axis to center it.