Wiper and Washer Switch Circuit: Procedure

READ VALUE USING TECHSTREAM (WINDSHIELD WIPER SWITCH)

Check the Data List for proper functioning of the windshield wiper switch.

COMBINATION SWITCH (WINDSHIELD WIPER SWITCH):

Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
Front Wiper OFF Switch	Front wiper OFF switch/ON or OFF	ON: Front wiper switch in OFF position OFF: Wiper switch not in OFF position	-
F Wiper LO Switch	Front wiper LO switch/ON or OFF	ON: Front wiper switch in LO OFF: Front wiper switch not in LO	-
F Wiper HI Switch	Front wiper HI switch/ON or OFF	ON: Front wiper switch in HI OFF: Front wiper switch not in HI	-
F Wiper AUTO Switch	Front wiper AUTO switch/ON or OFF	ON: Front wiper switch in AUTO OFF: Front wiper switch not in AUTO	-
F Wiper MIST Switch	Front wiper MIST switch/ON or OFF	ON: Front wiper switch in MIST OFF: Front wiper switch not in MIST	-
F Washer Switch	Front washer switch/ON or OFF	ON: Front washer switch ON OFF: Front washer switch OFF	-
Wiper Volume Position	Front wiper volume (sensitivity)/0 to 90 degrees	0 degrees/FR wiper volume "+" position 27 degrees/Switch is turned one notch towards the "-" side from the FR wiper volume "+" position 63 degrees/Switch is turned one notch towards the "+" side from the FR wiper volume "-" position 90 degrees/FR wiper volume "-" position	-
Ignition Switch	Engine switch signal/ON or OFF	ON: Engine switch on (IG) OFF: Engine switch off	-

The display is as specified in the normal condition.

OK → PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

NG: Go to next step

CHECK HARNESS AND CONNECTOR (WINDSHIELD WIPER SWITCH - BATTERY AND BODY GROUND)

Disconnect the L25 switch connector.

Fig 1: Identifying Windshield Wiper Switch And Battery Connector
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Measure the voltage according to the value(s) in the table below.

Standard voltage

Measure the resistance according to the value(s) in the table below.

Standard resistance

Tester Connection	Condition	Specified Condition
L25-8 (E) - Body ground	Always	Below 1 Ω

OK → REPAIR OR REPLACE HARNESS OR CONNECTOR

OK → PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE