IMP003 hardware.voltage returns 18V, VDDA unsoldered?

My IMP003 tells me the voltage is about 18.424 V while it should be close to 3V
My code: server.log("The voltage is: “+ hardware.voltage()+ " V”)
I placed the multimeter probe on the VDDA decoupling/bypass capacitor and it showed 3V.

What could be the problem?
Could it be that the VDDA pin is unsoldered?
What voltage do you expect when VDDA is unsoldered? Is that 18V?

What you get if VDDA is not connected is undefined, really. There is no supply to the analog circuits so who knows what might happen (this is also a prohibited state according to the ST datasheet, so you may also see chip damage).

hardware.voltage reads the internal reference voltage with the ADC. As this is a fixed voltage, this can be used to determine the VDDA supply.

If the reference reads very low, then you will see a very high hardware.voltage() reading.