Inspection Procedure

1. Check the indication condition of the P/S warning light while wiggling the power steering ECU connector and wire harness up and down, and right and left.

   OK: P/S warning light indication condition does not change. 

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: GO TO Next Step 

1. Using the intelligent tester, check for DTCs and confirm that there are no problems in the CAN communication system.

   OK: DTCs are not output. 

NG:  GO TO CAN COMMUNICATION SYSTEM

OK: GO TO Next Step 

1. Using the intelligent tester, check for DTCs and confirm that there are no problems in the multiplex communication system (BEAN).

   OK: DTCs are not output. 

NG:  GO TO MULTIPLEX COMMUNICATION SYSTEM (BEAN)

OK: GO TO Next Step 

1. Remove the ECU-IG LH fuse from the main body ECU LH.
2. Measure the resistance of the fuse.

   Standard resistance: 

   Below 1 Ω 

NG: REPLACE FUSE 

OK: GO TO Next Step 

1. Disconnect the A23 connector from the power steering ECU.
2. Measure the voltage of the wire harness connector.

   Standard voltage 

   STANDARD VOLTAGE SPECIFICATION
   
   

   Tester Connection	Condition	Specified Condition
   A23-9 (IG) - A23-5 (PGND)	Power switch ON (IG)	10 to 14 V

   Fig 1: Identifying Power Steering ECU Connector Terminal

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK:  GO TO step  7

NG: GO TO Next Step 

1. Measure the resistance of the wire harness connector.

   Standard resistance 

   STANDARD RESISTANCE SPECIFICATION
   
   

   Tester Connection	Condition	Specified Condition
   A23-5 (PGND) - Body ground	Always	Below 1 Ω

   Fig 2: Identifying Power Steering ECU And Body Ground

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER STEERING ECU - BATTERY) 

1. Check the P/S warning light status on the combination meter.

   OK: The P/S warning light is off. 

OK: END 

NG: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE