Possibly the lid switch. Sometimes dropping the lid down forcefully will make it start. If not, then lift lid, put your left hand through the gap between top of bowl and the top deck of machine in the right hand rear corner. You will feel the switch lever. On the lever is an adjustment screw, turn it about 1 full turn anti clockwise & try closing the lid and see if it starts.
Lincoln Appliance NZ, January 2016