ignition?

now, when i try to start my truck , the batt. acts like its dead and all i hear is a click. the motor doesn't even turn over. i tested my starter and my batt. both are good. i talked to my uncle and he said it could be the ignition switch. (need some help here) it also takes a few sec for the on poss. to kick in

Clean your battery terminals and check for a bad connection at both ends of the positive and negative battery cables. Remove the bolts from the cables at the battery ends and remove all corrosion. After cleaning dip the ends in baking soda and water then rinse with water. Coat the terminals, bolts, and battery post with petroleum jelly and re-assemble. A little corrosion can cause big starting problems.

hey thanx for your reply, i found out late that the batt. had a bad cell. but what gets me is that there is no way you can test for that.