Normal Operation

The wiper relay, located in the Battery Junction Box (BJB), is activated when the ignition is ON. The wiper relay provides voltage to the windshield wiper motor. The wiper/washer switch is mounted to the Steering Column Control Module (SCCM). The SCCM  commands the windshield wiper motor to activate the appropriate wash, low, high and intermittent modes through a Local Interconnect Network (LIN).

When the wiper/washer switch is in the HIGH position, the windshield wiper motor also receives ground which is hardwired directly through the SCCM  (bypassing the logic within the module). This fail-safe circuit makes sure that the windshield wipers function in HIGH speed mode in the event of a LIN  communication failure.

• DTC B1131:02 (Wiper Motor Module: General Signal Failure) - This DTC sets when the SCCM  determines a general signal failure has occurred on the LIN  .
• DTC B1131:08 (Wiper Motor Module: Bus Signal/Message Failure) - This DTC sets when the SCCM  determines a communication error has occurred on the LIN  . If this DTC is present and the windshield wipers do not park when the switch is turned to the OFF position, the cause of the concern is most likely the microprocessor inside the wiper motor. If this DTC is present and the windshield wipers park when the switch is turned to the OFF position, the cause of the concern is most likely a wiring concern in the LIN  .

This pinpoint test is intended to diagnose the following: 

• Wiring, terminals or connectors
• Wiper/washer switch
• Windshield wiper motor
• Rain sensor (if equipped)
• SCCM