Wiper Motor Will Not Operate In Any Switch Position

Ensure fuse is okay. Turn wiper switch to LOW speed position. If motor cannot be heard running, go to step 2). If motor can be heard running, check for output shaft rotation. If output shaft is not turning, replace motor. If output shaft is turning, check wiper drive linkage.
Ensure wiper switch is in LOW position. Connect a voltmeter between motor terminal No. 3 and ground strap. See Fig 1 .

Fig 1: Checking Voltage Between Terminal No. 3 & Ground
Courtesy of CHRYSLER MOTORS.
If less than one volt or no voltage is present, move negative voltmeter lead to negative battery cable. If voltage increase is noticed, problem is bad ground circuit. Ensure motor mounting is free of paint and that nuts and bolts are tight.
If there still is no voltage, problem is an open circuit in wiring harness or wiper switch. If voltage increase is minimal (3 volts), problem is faulty motor assembly. Disconnect motor wiring connector and replace fuse. If fuse does not blow, motor is defective. If fuse blows, switch or wiring is at fault.