Hello I am trying to get ADC working on the 16f684 for the first time. I actually have it working for VDD reference but I can't get the Vref working right. For my project I want two analog inputs plus the analog Vref input (AN0 - AN2) I am using PWM output as well on RC5 (CCP1)

Code:
PortA  =  %00000000 
TRISA  =  %00000111
PortC =   %00000000
TRISC =   %00000000
'ADC Registers
ADCON0 =  %11000001
ADCON1 =  %00000000
ANSEL  =  %00000111
It looks like everything is correct, (right justify, external vref, Fosc/2, ADon) and my three analog channels. The problem is that when I do a conversion from AN0 any voltage above 1.5 maxes out the ADRESH and ADRESL (all set to ones). My reference voltage is 12 volts and I'm using internal RC oscillator (4MHZ) which limits my ADC resolution to 7 bits.

I have changed my ADCS to FOSC/16 as recommended in the PDF and still have the same problem. It also seems that for AN0 when I apply a voltage above VDD the pic limits the voltage to VDD (using a 10K pot to set the voltage).