MSP430FR6989: Use P1.1 as input for External Voltage Reference (VeRef+) on launchpad

Part Number: MSP430FR6989

I am trying to use P1.1 as input for external VeRef. I have removed the S1 on the launchpad and connected the external voltage source of 2048 mV. I set the P1SEL0 and P1SEL1 to BIT1. I also set the ADC12MCTL0 TO ADC12VRSEL_4.

However, I am not able read from P1.1. I am getting a reading of around 2048 from P1.1 even when I ground it. How can I use the P1.1 in the MSP430FR6989 launchpad for VeRef. Should I set REFOUT to 0 and REFON to 0?

Regards

Vijay