When diagnosing the problem in the wiper motor circuit location of wires follow the wire color in the diagrams, power wires are larger and brighter than the ground wires. For voltage check usage of a grounded 12-volt test light on each terminal of a connector until brightly lit. If the wipers operating slow, check the battery state of charge and replacement date; if all is well recharge the battery to full; if the wipers are slow and the battery is good remove the wiper motor and give a manual push to the wiper arms to check for binding in the linkage and the pivot joints and apply some grease on the linkages and pivot joints before refitting the motor. In case the wipers continue to run slow, check for.dirty or corroded connections especially the ground; if they look okay then replace the motor. If non-operative wipers are encountered first look at the fuse, if the fuse is good attach a jumper wire from the wiper motor to the ground then test the wipers. If the motor runs continue to check and correct the ground and if the motor does not run check for voltage at the motor at the wiper switch at HI setting. If voltage is present, and the motor is bad, replace and remove it from the vehicle using jumper wires fused from the battery, inspect for the binding linkage, if good. If it still doesn't work, replace it-it may sound banal, but it is a recommendation that might save you from numerous troubles. If there is no voltage at the motor check to see if there is voltage at the wiper control module if there is test the switch for continuity if the switch is good the wiper control module may need to be replaced. For inoperative interval function check the wiring between the switch and wiper control module, if the wiring is fine then test the resistance of the knob with the delay control; if the knob resistance is within the range then replace the wiper control module. If the wipers have stopped at their last position when the switch is off then control voltage should be checked at the park feed wire of wiper motor connector when switch is off and the ignition is on and if there is no voltage then check for open circuit between motor and the fuse panel. If the wipers do not stop unless the ignition is turned OFF, remove the wiring from the wiper control switch; if the wipers stop, replace the wiper switch but in case they continue running, the limit switch of the motor is shot and the motor will have to be changed. If the wipers do not drop below the hood line, look for mechanical interference by the linkage and or the vehicle body if none, look at the wiring diagram and if the wiring is sound replace the wiper motor. For wiper motor replacement, remove the windshield wiper arms, pry of cover, straight nut and pull the arm assembly straight up. Subsequent to this, provided below is the process that needs to be followed: First of all, the cowl cover has to be removed fully, next, the electrical connector of the wiper motor has to be disconnected fully, and finally, the mounting bracket retaining bolts have to be detached fully. Swivel up the mounting bracket to uncover the motor retaining bolts; undo the nut that attends the linkage of the wiper arm to the motor, then withdraw the motor from its mounting bracket in the reverse manner of installation.
Posted by FordPartsGiant Specialist 
