Inspection Procedure

HINT: Start the inspection from the step 1 in case of using hand-held tester and start from step  2 in case of not using hand-held tester.

1. READ VALUE OF HAND-HELD TESTER 
   1. Connect the hand-held tester to the DLC3.
   2. Turn the ignition switch to ON and push the hand-held tester main switch ON.
   3. Select the item "STEERING ANGLE" in the DATA LIST and read its value displayed on the hand-held tester.
   4. Check that the steering wheel turning angle value of the steering angle position sensor displayed on the hand-held tester is changing when turning the steering wheel.

      OK: 

      Steering wheel turning angle value must be changing. 

   • NG: CHECK AND REPLACE ABSORBER CONTROL ECU(See  ELECTRONIC CIRCUIT INSPECTION PROCEDURE  ) 
   • OK: GO TO NEXT STEP. 
2. INSPECT ABSORBER CONTROL ECU 
   1. Remove the absorber control ECU with the connector still connected.
   2. Turn the ignition switch to ON.
   3. Measure voltage between terminal A22 -1 (+B) and A22 - 14 (GND) of the absorber control ECU.
      Fig 1: Measuring Voltage Between Terminals A22-1 & A22-14

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: 

      Voltage 10 - 14 V 

   • NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
   • OK: GO TO NEXT STEP. 
3. CHECK HARNESS AND CONNECTOR (STEERING SENSOR) 
   1. Disconnect the steering sensor connector.
   2. Turn the ignition switch ON.
   3. Measure voltage between terminal 1 (IG1) and 2 (ESS), 2 (ESS) and 9 (BAT) of the steering sensor harness side connector.
      Fig 2: Measuring Voltage Between Terminals IG1 & ESS And ESS & BAT

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: 

      Voltage 10 - 14 V 

   • NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
   • OK: GO TO NEXT STEP. 
4. INSPECT STEERING SENSOR 
   1. Disconnect the steering angle sensor connector.
   2. Apply battery positive voltage between terminals 1 (IG1) and 2 (ESS), 2 (ESS) and 9 (BAT).
      Fig 3: Applying Battery Voltage Between Terminals IG1 & ESS And ESS & BAT

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   3. Connect the oscilloscope to the terminals 4 (SS2+) and 12 (SS2-) of the steering angle sensor.
   4. Turn the steering column shaft slowly and check the signal waveform.

      OK: 

      Fig 4: Steering Sensor Signal Waveform

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   HINT: The above signal waveform does not repeat ON and OFF regularly and this ON-OFF interval changes case by case according to the data.

   • NG: REPLACE STEERING SENSOR 
   • OK: CHECK AND REPLACE ABSORBER CONTROL ECU (See  ELECTRONIC CIRCUIT INSPECTION PROCEDURE  )