Countax 600H Garden Tractor?

Electromagnetic clutch is not engaging when the dash switch is on. The flickering light on the panel is showing when the switch is on. Local dealer has had the machine twice in the last year and got it working but is vague when asked what the problem is. Had the machine back for 4 weeks and the same problem has arisen again. Anyone got any ideas in this regard

John
June 2011