The windshield wiper motor in a Volkswagen Jetta controls the function of the windshield wipers. Because of this, it's important that you check the motor periodically to make sure it is working normally. A motor that fails can leave you with no way to clear the windshield during inclimate weather, which in turn creates a dangerous driving situation. Replacement motors can be purchased from most auto parts stores.
Open the bonnet of your Jetta and unplug the electrical connector running to the wiper motor, which is mounted on the firewall.
Unbolt the wiper motor from the firewall using a socket wrench.
Slide the wiper motor off the wiper linkage and firewall.
Orient the replacement wiper motor so that the wiper motor easily slides onto the end of the shaft on the wiper linkage.
Thread and tighten the bolts that hold the wiper motor in place using the socket wrench.
Reconnect the electrical connector.