When you clear the codes on an OBD2 car it has to "Cycle" before you can get the emissions test done. Now I can see on my code scanner that there are 5 readiness test that I can Monitor.

Heater O2...
EGR..
I forget what the other 3 readiness tests are

Now I heard that you dont need to have all 5 say OK 3 out of 5 would be OK? Any truth in this?