Garage door opener - turn light on without opening the door
You can easily connect the old motion sensor to the NodeMCU , you see,
sensors in general have two wires, one as income voltage and the other one is output voltage, in normal way with no detection at all , output voltage is 0V for analoge sensors and [1input voltage]* as output,

if you want to hack the old wall unit:

disconnect it from power, let it for some time to make sure no holding charges are in capacitors ,

unlock it with screwdriver, search for the sensor

as it is a motion sensor , it should be behind black plastic cover, but it is not necessarily,

Next step is to determind what voltage it operate at , &quot;if it is AC driven the it will be 110v for US or 220v for worldwide and you should use adapter to 5v&quot;, if its DC driven then no worries&quot;,

after that you connect postive terminal of sensor to the voltage and the other black terminal to the input of the NodeMCU, program that pin as input, when ever a detection is happen, a signal will be sent to the nodeMCU, after that the NodeMCU will send signal to the light conductor to connect and turn on the lights,