2000 eclipse driver window wont roll down

First determine if it the switch or the motor. Use a multimeter to test the switch or a small battery to test the motor. Then replace whichever is not working.

Disconnect the motor connector and put a test light in series with the circuit. If it illuminates when the switch is actuated in both direction than its the motor. If not, than work your way back through the circuit. A dmm does not give an accurate depiction of the circuit. Do not use one.

a good multimeter can be used to measure resistance across the swtich. this will show if it is working. it can also probe the connecter to see if there is power going to the motor.

Not good to use a test light on OBDII cars. Wouldn't recommend it especially on if it maybe high impedance circuit and usually it is. You could let out the magic white smoke and you may end up buying a new body control module. Use a Digital Multimeter, check for voltage with Key switch "on". Should be around 5 volts switching the window switch on. Then check for resistance with key off. The Resistance should be kinda high, not reading "0.L" while using the switch.

FYI, the resistance of an incandescent 12v test light is ample for testing any circuit, minus probing modules. Also, working for GM myself, on their GM Service Information website, its specific instructions dictate using a test light. Furthermore, the test light is one of the most valuable tools to any career mechanic for diganostics. Thanks again for that lesson on diagnosing a vehicle, champ.

Also, if one decides to check a circuit for excessive resistance and none is present that doesn't tell you the fact that a wire could be broken and have only one strand still completing it, which in turn would not necessarily show it self in such a check. Also if you were to check the resistance of the switch in use with power taken away from the circuit obviously, you should have no more than 0.5 ohms. To continue, with power removed, and GM uses a low-reference circuit with the DDS and the BCM in conjunction,therefore a dmm should real OL.

FYI, GM and Mitsubishi are two different car companies. There was only one time I saw an Mitsubishi symbol on a GM and that was on a cam angle sensor on an 95ish caprice. I personally wouldn't use a test light, although you never know when you work on different cars other than GM. Therefore GM is not the say so for all automotive technicians. It is only their methods. Just like it's Honda/Acura's method of replacing an 12V battery while the car is running. Thank you for the lesson on diagnosing a vehicle, champ. :)