How the Circuit Works: Notes

The wiper/washer system is a multiplex controlled system. The combination switch control unit, MICU, and relay control module are the main operation controls of the wiper/washer system. The washer motor relay, intermittent wiper relay, and windshield wiper high relay are incorporated in the relay control module.

Testing the control unit components and reading the Diagnostic Trouble Codes (DTCs) within the multiplex integrated control system can be done by using an HDS Tester. There are more than 80 multiplex system DTCs. The wiper motor and washer motor can still be tested manually without an HDS Tester.

Refer to the WIPER SYSTEM/WASHER SYSTEM Wiper/Washer DTC Troubleshooting for testing and troubleshooting procedures.