Hi Thomas,

I have seen that the TRIS is OK, but here are some questions to you:

1.  What is your VDD doing? (VDD = 4.06V?)

2. Change the PIC. It may be corrupt because of an prior latchup.

3. Wouldn't it be better to set the TRIS-Bits before you start the AD-Module? Th
is
might not have an effect on the solution of your problem. But better you exclude
any doubts.

4. Let the sample time be at least 40us.

6. What is your Clk-Freq? At 20MHz you will have problems with 8Tosc.

7. You enable PIE1,ADIE. Why? And why do you clear the ADIR. You dont use it.

8. IMHO the input filter is not so essential as it is discussed here. More
essential is the value of the resistor, what was discussed before.

I hope something is working. Point 4 is the most important!!!