Output when Vs removed from ST pin?

Q 

I am attempting to use the self-test function on the ADXL326.

I see my X, Y & Z axis measurements change when the self-test pin is asserted.

However, they do not change back when the self-test pin is cleared – is this
expected ?

 

A 

Once Vs is removed from the ST pin, readings should return to their
original state.

I tested this with the ADXL327. When I remove Vs from ST, the output reverts
back to the original state.

With Vs = 3V:

When ST is not asserted (floating), X, Y and Z are 1.48V, 1.4V and 2.02V,
respectively.

When ST is asserted (connected to Vs), X, Y and Z are 1.12V, 1.81V and 2.72V
respectively.

When ST is removed, X, Y and Z return to 1.48V, 1.4V and 2.02V, respectively.

One possible cause may be that ST input was exposed to an over-voltage
condition?