How do you test if power is reaching a window motor?

[Wrench97]

You can have voltage at a test point, but if you don't have the require POWER you have nothing. A typical 12V test light draws about 250mA (1/4A), so if the light is bright, you know you have at least that much power available.


Okay, ADVANCE OHM'S LAW. So you want to power up a device, but you don't want it to draw too much power (for whatever reason). If you put a test light in SERIES between the voltage source (battery) and the "device under test" the maximum amount of power that can be consumed is 250mA. Need more power ? Make you own "heavy duty" test light using something like a headlight bulb. Those will draw (or limit) to about 4A-5A.

That's why as I stated you check the circuit loaded with the motor plugged in those connectors are quite large and easy to back probe without damage.
If you have power and ground at the motor with it plugged in and it does not go whirrrr it's going to be bad.

Unless it's a newer setup with power/ground and a lin bus control wire that is then you may need the Pico scope................................