Start by unplugging the control box and plugging it back in. If this does not work try adjusting the bedknife on your T4, if there is too much blade contact this can cause the control box to overload and fault. Inspect your machine to ensure there are no obstructions blocking the helix blade and that the helix blade and bedknife are clean. Make sure you are running your machine off of a minimum 14 AWG extension cord and that it is no longer than 25 feet. If this does not solve the issue please contact our Technical Support line at 1-888 254 3204.