The best way to check to see if you are getting connection is to check for volt drop across the contact tips when the are closed. You also need to check the opposite contactor for volt drop on the normally closed tips. If I remember correctly there is a 14 or 16 gauge wire connected to one of the buss bars the sends a signal to the control card so it knows there is a connection being made. The problem could be in the small gauge wire or connector at the card.