How can I fix my Fisher Paykel Top Load GW711 ?

My F & P top load GW711 washing machine will go through the wash cycle fine till it is to do first spin and rinse ( also Final spin) it will stop with water remaining in the bowl and will not fully drain out , I can keep turning power on and off and advancing program to rinse LED and it will pump a little water out each time until it is empty and will then spin and continue fine until it gets to final spin and same occurs again and I have to through process again. Can you tell me how to prove if it is water pump or electrical board or some thing else please.