Testing a switch or a motor wrongly could have irreversible effects, I'm guessing.
There must be a local mechanic/electrician, who fit car alarms? All they need to do is locate the positive and negative wires on either the motor or switch, and test them using a multi meter, or power supply.
Be careful not to buy a used motor or a switch, even refurbished ones woudl be dubious in the long run.