What Is a Wiper Relay Switch?

Safety and control of your car or truck depend on your windshield wiper systems. They run at various speeds, with an option to spray water with a cleaning solution for bugs and mud.

Wiper Relay Switch

  • Although many vehicles do not have them, a wiper relay switch operates when you turn on the wipers. It closes contacts that provide voltage to the windshield wiper motor.

Internal Relay

  • In some vehicles, the wiper relay switch is inside the actual windshield wiper motor. If it fails, the entire motor needs to be replaced, as you can't get parts to fix it.

Second Wiper System

  • Some vehicles have a second wiper on the rear window. This wiper could be controlled by a wiper relay switch.

Direct Controls

  • Many wiper motors don't need much current to run. Their wiper controls connect directly to the wiper motor without a relay.

Washer Systems

  • The washer systems associated with your windshield wiper control switch usually doesn't need a relay. It wires direct from the control to the pump.

Intermittant Wiper Relay

  • Some intermittent windshield wiper systems use a relay controlled by a timer. These relays may be inside the actual windshield wiper motor also.