The cable is fully extended and won't retract. I've had a look but there seem to be insufficent screws to enable separating main top and bottom plastic mouldings (which seems necessary to gain access). Removing the dust bag reveals 2 screws at front of machine and 2 more about halfway back. Nothing else. Rtied removing them but something is holding casing together. Do the wheels come off? If so, how?
I expect you've thrown it by now,but I've just had the reverse problem, cable jammed short. You'll have to remove the "Switch covers", be very careful as there are small Plastic lugs inside for hingeing, I broke mine and had to do a "Chips Mod", underneath these you will find the remaining 2 screws, 1 under each cover. There is another screw in the hole where the cable goes into the machine, ignore it ,as it does'nt hold the base together.
Good Luck!