Inspection Procedure

1. Remove the ultrasonic sensor.
2. Measure the resistance of the sensor.

   Standard resistance 

   TESTER CONNECTION SPECIFIED CONDITION CHART
   
   

   Tester Connection	Condition	Specified Condition
   S (D2-2) - E (D2-1)	Always	600 to 1,200 kΩ

   NOTE: Set the tester to the 100 kΩ range before performing the measurement.
Fig 1: Inspecting No. 1 Ultrasonic Sensor
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPLACE NO. 1 ULTRASONIC SENSOR (FRONT LEFT SENSOR) 

OK: Go to next step 

1. Disconnect the Q37 ECU connector.
2. Disconnect the D2 sensor connector.
3. Measure the resistance of the wire harness side connectors.

   Standard resistance 

   TESTER CONNECTION SPECIFIED CONDITION CHART
   
   

   Tester Connection	Condition	Specified Condition
   S4 (Q37-6) - S (D2-2)	Always	Below 1 Ω
   E4 (Q37-19) - E (D2-1)	Always	Below 1 Ω
   S4 (Q37-6) - Body ground	Always	10 kΩ or higher
   E4 (Q37-19) - Body ground	Always	10 kΩ or higher

Fig 2: Checking Wire Harness (Clearance Warning ECU - Ultrasonic Sensor)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: REPLACE CLEARANCE WARNING ECU