Pull the front wheels off and see if the plastic cogs are worn - should look like a bicycle spoke. Mine broke last weekend when the cable caught on I I Hook for a gate - pulled the cable out of the handle. Waiting for a $27.00 replacement from EBay . Sears wanted $54.00 for the same handle and cable .
Your spring could of come off under the plastic protective cover or your belt snapped or came off the pulley - its always simple fix .
