Hi Vaidyanathan,
The inputs can actually float to any value, so trying to measure floating inputs is meaningless. Even if you should short the two inputs together the measurement is meaningless, that is because there is a common mode input restriction at a gain of 128. The analog input must be within the range of AVDD-1.5V and AGND+1.5V for gains of 64 and 128. When you physically touch the terminals (watch out for ESD) you change the input voltage to some other level, but in time it could once again float back to the higher voltage level.
If you connect the inputs to a bridge, there may be some offset. This could be due to the ADC or it could be that the bridge is slightly unbalanced. The SELFOCAL will take care of ADC offset. However, if there is a connection problem with the bridge, or the reference input, you may see a full-scale reading. It is always a good idea to measure the voltages at the ADS1232 input pins referenced to AGND. If the excitation is 5V to the bridge, and the the bridge is balanced, then you should read approximately AVDD/2 (2.5V) at AIN+ and AIN- (referenced to AGND). The ADC result code should be near zero codes (with the possible offset).
Best regards,
Bob B