Hi JDM160,
I have never used weak pull ups before, however; I do not see in you code where you enabled them. If I understand the data sheet correctly, and it is very possible I do not . . . WPUA=%00110111 should enable them on portA 0,1,2,4,5. with A3 configured automaticly if used as mclr and not available if configured as an I/O. The data sheet says weak pullups are disabled after power on reset.page 32.

Joe