The request is to see if the motor is plugged in or not, yes?
I faced a similar problem for a product, to detect if a display panel was plugged in. My solution? Use a current mirror to pass a small sensing current into the load, like so:
simulate this circuit – Schematic created using CircuitLab
Q1 sinks a small current from the connected load, turning on Q2 and bringing signal LOAD_PRESENT_N low. If there is no load connected, Q1 and Q2 will be off, so LOAD_PRESENT_N will be high.
Ideally you want to use a matched pair for Q1/Q2, but for this kind of basic use separate NPNs should be ok.