Inspection Procedure

1. Check that the following vehicle stability control system DTC is not output.

   Result 

   RESULT REFERENCE
   
   

   Result	Proceed to
   DTC (C1231/31) is not output	A
   DTC (C1231/31) is output	B

B: REPAIR CIRCUITS INDICATED BY OUTPUT DTCS  (See DTC C1231/31 STEERING ANGLE SENSOR CIRCUIT MALFUNCTION )

A: Go to next Step 

1. Connect the Techstream to the DLC3.
2. Turn the engine switch on (IG).
3. Turn the Techstream on
4. Enter the following menus: Body Electrical / AFS / Data List.
5. Read the display on the Techstream

   AFS (AFS ECU) 

   DATA LIST - AFS (AFS ECU)
   
   

   Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
   Steer Sens Sig	Steering angle sensor signal value / -384° to 382 5°	Approx 0° (When steering wheel is straight)	-

   OK: Condition sign can be displayed. 

   Result 

   RESULT REFERENCE
   
   

   Result	Proceed to
   OK (When checking from Problem Symptoms Table)	A
   OK (When checking from Diagnostic Trouble Code Chart)	B
   NG	C

B: REPLACE AFS ECU  (See AFS ECU  )

C: Go to step 3 

A: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE  (See PROBLEM SYMPTOMS TABLE  )

1. Disconnect the J23 steering angle sensor connector.
2. Disconnect the A27 AFS ECU connector.
3. Measure the resistance according to the value (s) in the table below

   Standard Resistance 

   STANDARD RESISTANCE SPECIFICATION
   
   

   Tester Connection	Condition	Specified Condition
   J23-7 (SS1-) - A27-8 (SS-)	Always	Below 1 Ω
   J23-8 (SS1+) - A27-7 (SS+)	Always	Below 1 Ω
   A27-8 (SS-) - Body ground	Always	10 kΩ or higher
   A27-7 (SS+) - Body ground	Always	10 kΩ or higher

Fig 1: Identifying J23 Steering Angle Sensor Connector
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next Step 

1. Reconnect the A27 AFS ECU connector
2. Measure the voltage according to the value (s) in the table below

   Standard Voltage 

   STANDARD VOLTAGE SPECIFICATION
   
   

   Tester Connection	Switch Condition	Specified Condition
   A27-7 (SS+) - A27-8 (SS-)	Engine switch on (IG)	Pulse generation

Fig 2: Identifying A27 AFS ECU Connector
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPLACE AFS ECU  (See AFS ECU  )

OK: REPLACE STEERING ANGLE SENSOR  (See STEERING ANGLE SENSOR )