Hotpoint Intelligent Care Fridge Freezer?

Having bit of difficulty getting my fridge freezer to stay cool I have stripped the interior back board of the fridge freezer and noticed the fan does not seem to be moving. I switched the fridge freezer off and then back on again and noticed the fan moves for no more than 3seconds and then stops. At the minute the fridge freezer is making the usual sound that it makes but no air is getting into the fridge compartment. The freezer compartment is slowly defrosting.