Starter Relay problems of the 2001 Mazda Tribute

While driving and making a left hand turn vehicle suddenly died, no prior warning. There was not steering or braking. Consumer had to stop vehicle with emergency brake. Vehicle was stuck in traffic. Consumer had vehicle towed to dealer ,and dealer replaced electrical relay system. However, problem reoccurred on July 3, 2001 while traveling at 45 mph on a decline vehicle died, and emergency brake would not stop vehicle. Eventually emergency brake kicked in and stopped vehicle. Consumer stated that when trying to start again, there were no transmission lights, and would not go into gear. Consumer had vehicle towed to dealer, and they could not duplicate problem. Please provide any further information.