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This can be found either from information in your owner's manual or on the Internet. You should refer to your electrical schematic for help. You want to make sure that there are no breaks in the connection from the fuse box to the switch. If you did not find a schematic, it might be easier to trace the wiring from the switch back to the fuse box to look for any breaks in the connection. Attach the leads of the multi-meter to where the electrical wires come into the switch and set the meter to D/C volts. It should read 12 volts. This is the path that a signal will travel to move your window when you press the switch. Any breaks or loose connections in this path will prevent your motor from functioning properly. Attach the leads of the multi-meter to where the electrical wires come into the motor. Again, set it to D/C volts and it should read 12 volts. If there are any loose or corroded connections in the circuit they will disrupt the signal and cause your window to malfunction. Push any connectors or wiring harnesses together tightly, and clean any corrosion away with a wire brush or similar tool. . If your problem was in the circuitry and is now fixed, then your window should freely roll up and down without any restrictions or delays.

Summary:
Find an electrical schematic of your vehicle. Trace the wiring from the fuse panel to the switch. Use a multi-meter to confirm that the switch is getting 12V of power. Trace the wiring from the switch to the motor. Use the multi-meter to confirm that the motor is getting 12V of power. Look for any interrupted voltage caused by a loose connector or corrosion. Fix the connector or corroded areas. Test the window again.