compare roles to trace problem

Question: hi

i have a requirement such that there are 2 roles , A and B if i use role A i get what i need and if use Role B it does not work for the requirement , so i need to find out which object that is different in these 2 roles is causing problem, so i did a compare between these 2 roles , but i get 80+ objects that are different , now should i try each and every object thats different and try the requirement for the test user everytime to trace the problem or is there any other method

Answer:
When you use Role B did you do an SU53 to check for the auth failure?
Have you run a trace (ST01) of the successful action and compared it to a trace of the failed one?