Rain Sensor Circuit: Procedure

1. Disconnect the H51 windshield wiper relay assembly connector.
2. Disconnect the T1 rain sensor connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   H51-14 (MPX1) - T1-1 (MPX)	Always	Below 1 Ω
   T1-1 (MPX) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Disconnect the T10 roof console box assembly.
2. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   T10-1 (IG) - T10-21 (GND2)	Engine switch on (IG)	11 to 14 V

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   T1-2 (ES) - T10-21 (GND2)	Always	Below 1 Ω
   T1-4 (SIG) - T10-14 (IG2)	Always	Below 1 Ω

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Reconnect the T10 roof console box assembly.
2. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   T1-4 (SIG) - T1-2 (ES)	Engine switch on (IG)	11 to 14 V

NG → See step   8 

OK: Go to next step 

1. Reconnect the T1 rain sensor connector.
   Fig 1: Identifying Rain Sensor Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Connect an oscilloscope to the rain sensor connector.
3. Check for pulses.

   OK

   Tester Connection	Condition	Specified Condition
   T1-1 (MPX) - T1-2 (ES)	Engine switch on (IG)	Pulse generation

   TEXT IN ILLUSTRATION
   
   

   *a	Component with harness connected (Rain Sensor)

NG → See step   7 

OK → See step   6