Low Speed Operation

When the wiper switch is in the low speed position, battery positive voltage is applied through the switch internal resistor and the wiper switch low signal circuit to the body control module (BCM). In response to this signal, the BCM energizes the wiper ON/OFF relay by applying battery voltage through the windshield wiper switch signal 2 circuit to the coil side of the relay. This allows battery positive voltage from the WIPER fuse to flow through the input side of the ON/OFF relay and out to the switch side of the HI/LO relay. Since the wiper HI/LO relay is de-energized and its switch contacts are normally closed to the low speed control circuit of the windshield wiper motor, the motor will operate at low speed.

Wiper motor low speed operation and the wiper ON/OFF relay can also be commanded ON/OFF by using a scan tool .