Step 1 – Inspect both drive wheels to see if sticks, toys, accumulated mud, or mulch is slowing down one of the wheel’s rotation. Clean well and send the mower to mow on a leveled area. Did you correct the curved lines, meaning it drives in a straight line?
If Yes – Problem solved.
If No – Proceed to Step 2.
Step 2 – Are RoboGrips installed on the drive wheels?
If Yes – Send the mower to mow on a relatively leveled area. Mark which direction it curves to – right or left. Now swap the RoboGrips between the wheels, send it to mow on the same leveled area and see if now curves to the other side. If it does, it means the RoboGrips cleats have begun to wear down.
Typically the right side RoboGrips wear out faster due driving on sidewalks concrete on parts of the Edge mowing route.
If No – Proceed to Step 3.
Step 3 – Is the mower SW version 303.49 or above?
If Yes – Proceed to Step 4.
If No – SW version needs to be upgraded. Consult with customer support.
Step 4 – Lift the rear of the mower and put a brick or an extra drive wheel underneath, to support it and keep both drive wheels above ground, so when tested they spin in the air. Use mower’s service menu to test drive motors. Did the drive motors test result in “Passed” message?
If Yes – Proceed to Step 5.
If No – Perform the test a few more times to see if it passes or fails. Then Replace the Faulty Drive Motor.
Step 5 – Passing drive motors test means there must be something physical slowing down one of the drive wheels – inspect and clean as needed, then send the mower to mow on a leveled area and see if problem resolves. Does mower now drive in straight lines?
If Yes – Problem solved.
If No – Replace the Faulty Drive Motor. If mower curves to the right, replace left drive motor and vice versa. If this didn’t resolve the issue, proceed to Step 6.
Step 6 – Replace the Main Board. Did it fix the curved lines?
If Yes – Problem solved.
If No – Consult with customer support.